// Numbas version: finer_feedback_settings
{"name": "Jean jinhua's copy of 0: Getting Started with Numbas", "feedback": {"showtotalmark": true, "advicethreshold": 0, "allowrevealanswer": true, "feedbackmessages": [], "showactualmark": true, "showanswerstate": true, "intro": "", "enterreviewmodeimmediately": true, "showexpectedanswerswhen": "inreview", "showpartfeedbackmessageswhen": "always", "showactualmarkwhen": "always", "showtotalmarkwhen": "always", "showanswerstatewhen": "always", "showadvicewhen": "never"}, "timing": {"allowPause": true, "timeout": {"action": "none", "message": ""}, "timedwarning": {"action": "none", "message": ""}}, "allQuestions": true, "shuffleQuestions": false, "percentPass": 0, "duration": 0, "pickQuestions": 0, "navigation": {"onleave": {"action": "none", "message": ""}, "reverse": true, "allowregen": true, "showresultspage": "oncompletion", "preventleave": true, "browse": true, "showfrontpage": true}, "metadata": {"description": "<p>6 questions which introduce the student to the Numbas system.</p>\n<p>rebelmaths</p>", "licence": "Creative Commons Attribution 4.0 International"}, "type": "exam", "questions": [], "showQuestionGroupNames": false, "question_groups": [{"name": "", "pickingStrategy": "all-ordered", "pickQuestions": 0, "questions": [{"name": "Input 1", "extensions": [], "custom_part_types": [], "resources": [], "navigation": {"allowregen": true, "showfrontpage": false, "preventleave": false, "typeendtoleave": false}, "contributors": [{"name": "Christian Lawson-Perfect", "profile_url": "https://numbas.mathcentre.ac.uk/accounts/profile/7/"}], "functions": {}, "tags": ["Numbas", "answers", "entering", "fields", "input", "introduction", "mathematical notation", "numbas", "parts", "practice mode", "reveal", "submit"], "advice": "", "rulesets": {}, "parts": [{"prompt": "<p>Questions are often split into parts.</p>\n      <p>In each part you will see various input fields for your answers.&nbsp;</p>\n      <p>This is the first part and contains one question for you to answer .</p>\n      <p>It will be clear from the question what you need to enter in each field.</p>\n      <p>For example, a question could be:</p>\n      <p>$2+2=\\;$[[0]]&nbsp;(enter a number)</p>\n      <p>You are expected to enter the answer and then press the Submit part button.</p>\n      <p>Try it: enter the correct value; note that a box appears showing your input; press <em>Submit part</em> - a tick appears. Brilliant!</p>\n      <p>Now enter an incorrect value. Press <em>Submit part</em> and a cross appears. Note the <em>Show Feedback</em> button; clicking on that gives a more detailed feedback - in this case there is not much to say!</p>\n      <p>This is the sort of feedback you get in practice mode.</p>\n      <p>Try putting in <code>2+2</code> as your answer and see what happens as well.</p>\n      <p>You will be given an error message; click on <em>OK</em> and continue.</p>\n      <p>So you must be careful and always check that the answer in the input field is what you expect it to be before you move on.</p>\n      <p>Pressing the <em>Reveal answers</em> button at the bottom of the screen gives you the answers for all parts and usually also gives you a full solution for each part. This is only available in Practice mode and certainly not available in Exam mode.</p>\n      <p>Also note that in Practice mode you have available a button at the bottom labelled <em>Try another question like this one</em>. This is useful for you to try other versions of the question, if it is randomised. This question is not randomised, so you will get the same one back again!</p>", "gaps": [{"integerpartialcredit": 0.0, "integeranswer": true, "maxvalue": 4.0, "minvalue": 4.0, "marks": 1.0, "type": "numberentry", "showPrecisionHint": false}], "type": "gapfill", "marks": 0.0}, {"prompt": "<p>This is the second part of this example and it contains 2 questions.</p>\n      <p>Enter your answers for both and then press <em>Submit part</em> for both.</p>\n      <p>Note that your input in mathematical notation is displayed next to your input so you can check it has been interpreted as you intended.</p>\n      <p>$x+x=\\;$[[0]]&nbsp;(Enter a multiple of $x$ )</p>\n      <p>Enter your answer as <code>2*x</code>. You could just enter <code>2x</code> without the <code>*</code>, but we advise you to use <code>*</code> for all multiplications as there are some cases where the meaning of your input would be ambiguous otherwise.</p>\n      <p>Simplify the following expression. Once again you see your answer in the best possible mathematical notation next to your input.</p>\n      <p>This check becomes more important when you input more complicated expressions - see later questions.</p>\n      <p>$2x-x+y-2y=\\;$[[1]]</p>\n      <p>Try getting one right and one wrong and see the sort of feedback you get. The greyed-out tick indicates that you were awarded some of the available marks but not all.</p>\n      <p>Also try inputting <code>x+x</code> for the answer to the first question in this part and see what happens after you submit.</p>\n      <p>Note the red exclamation marks next to the input field when you enter something the system does not like or you have submitted without answering the question. Move the cursor over the mark and you will get a message saying what the problem is.</p>\n      <p>The <em>Submit all parts</em> button at the bottom allows you to submit all your answers at once without submitting each part separately. In this case, the answers in both parts will be submitted.</p>", "gaps": [{"notallowed": {"message": "<p>Simplify the expression please!</p>", "showstrings": false, "strings": ["+"], "partialcredit": 0.0}, "expectedvariablenames": [], "checkingaccuracy": 0.001, "vsetrange": [0.0, 1.0], "showpreview": true, "vsetrangepoints": 5.0, "checkingtype": "absdiff", "marks": 1.0, "answer": "2*x", "checkvariablenames": false, "type": "jme"}, {"notallowed": {"message": "<p>Simplify further!</p>", "showstrings": false, "strings": ["+"], "partialcredit": 0.0}, "expectedvariablenames": [], "checkingaccuracy": 0.001, "vsetrange": [0.0, 1.0], "showpreview": true, "vsetrangepoints": 5.0, "checkingtype": "absdiff", "marks": 1.0, "answer": "x-y", "checkvariablenames": false, "type": "jme"}], "type": "gapfill", "marks": 0.0}], "statement": "\n  <p>This example explains how you enter your answers and submit them.&nbsp;</p>\n  <p>This example and the others are in practice mode - you will be given information on whether or not you have the answer correct or not.&nbsp;</p>\n  <p>Exam mode does not give you this information.</p>\n  <p>It is very important that you submit all your answers. If you do not your results will not be recorded. &nbsp;Note that the list of questions in the exam on the left of the window gives information on whether or not you have completed a question. For each question the marks you have gained by submitting are shown there, so if nothing is shown you have not attempted the question.</p>\n  <p>Go to the next question. You can then come back. Note that until you quit the exam for good you can go back to any question and change your answers if you want to.</p>\n  ", "variable_groups": [], "progress": "in-progress", "type": "question", "variables": {}, "metadata": {"notes": "", "description": "<p>Entering numbers and algebraic symbols &nbsp;in Numbas.</p>", "licence": "Creative Commons Attribution 4.0 International"}, "showQuestionGroupNames": false, "question_groups": [{"name": "", "pickingStrategy": "all-ordered", "pickQuestions": 0, "questions": []}]}, {"name": "Input 2", "extensions": [], "custom_part_types": [], "resources": [], "navigation": {"allowregen": true, "showfrontpage": false, "preventleave": false, "typeendtoleave": false}, "contributors": [{"name": "Christian Lawson-Perfect", "profile_url": "https://numbas.mathcentre.ac.uk/accounts/profile/7/"}], "functions": {}, "tags": ["Fractions", "Numbas", "decimals", "fractions", "input", "introduction", "numbas", "numbers", "tolerance", "whole numbers"], "advice": "<p>No advice available.</p>", "rulesets": {}, "parts": [{"prompt": "<h3>Whole numbers</h3>\n        <p>This is an example of a randomised question - the next time you use this example you will be asked to do a different calculation.</p>\n        <p>Find the result of this calculation:&nbsp;</p>\n        <p>$\\var{a}\\times\\var{b}+\\var{c}=\\;$[[0]]</p>\n        <p>You must input a whole number; for example, if the answer were $2$ then you could input <code>2</code> or <code>2.0</code> - try both forms.</p>", "gaps": [{"minvalue": "a*b+c", "type": "numberentry", "maxvalue": "a*b+c", "marks": 1.0, "showPrecisionHint": false}], "type": "gapfill", "marks": 0.0}, {"prompt": "<p>Sometimes I could force you to enter a whole number not in decimal form. But this should be no problem as you will be warned.</p>\n        <p>Enter the result of this calculation, but do not enter it as a decimal.</p>\n        <p>$\\var{a}\\times\\var{b}+\\var{c}=\\;$[[0]]</p>\n        <p>Enter the correct answer as a decimal, i.e. in the form <code>2.0</code>, and see what happens.</p>", "gaps": [{"notallowed": {"message": "<p>Do not enter your answer as a decimal. Enter as a whole number without the decimal point.</p>", "showstrings": false, "strings": ["."], "partialcredit": 0.0}, "expectedvariablenames": [], "checkingaccuracy": 0.001, "vsetrange": [0.0, 1.0], "showpreview": true, "vsetrangepoints": 5.0, "checkingtype": "absdiff", "marks": 1.0, "answer": "{a*b+c}", "checkvariablenames": false, "type": "jme"}], "type": "gapfill", "marks": 0.0}, {"prompt": "<h3>Decimals</h3>\n        <p>Many calculations will result in numbers which must be entered in decimal notation.</p>\n        <p>I will always ask for the decimal to be input to a certain number of decimal places.&nbsp;</p>\n        <p>Often there is a small tolerance built in so that if you get the result wrong by 1 in the last decimal place then it will be marked as correct.&nbsp;</p>\n        <p>But accuracy is important - so make sure that you get the calculations correct.</p>\n        <p>For example:&nbsp;</p>\n        <p>Input $\\displaystyle \\frac{\\var{a1}}{\\var{b1}}$ as a decimal correct to 2 decimal places here: [[0]]</p>\n        <p>Try putting in the correct value and submitting. Then vary the last decimal place by 1 either way and submitting, and then the last place by 2 either way and submitting.</p>\n        <p>Try putting in the fraction as it is (i.e. $\\var{a1}/\\var{b1}$ ) and see what happens.&nbsp;</p>\n        <p>The system gives an error message, as what you have put in is not a decimal representation of a number. But you can always re-enter.</p>\n        <p><strong>So be careful - always check after submitting your answer that the input field contains the answer that you thought you input.</strong></p>", "gaps": [{"minvalue": "{ans1-tol}", "type": "numberentry", "maxvalue": "{ans1+tol}", "marks": 1.0, "showPrecisionHint": false}], "type": "gapfill", "marks": 0.0}, {"prompt": "<h3>Fractions</h3>\n        <p>You will find that some questions may ask you to input fractions and not decimals.</p>\n        <p>For example:&nbsp;</p>\n        <p>Find the following sum as a fraction:</p>\n        <p>$\\displaystyle \\frac{1}{\\var{a1}}+\\frac{1}{\\var{b1}}=\\;$[[0]]</p>\n        <p>(input as a fraction and not a decimal)</p>\n        <p>You input the answer as <code>{a1+b1}/{a1*b1}</code>.</p>\n        <p>Try inputting the decimal version of this to as many places as you like, and see what happens.</p>", "gaps": [{"notallowed": {"message": "<p>Simplify into a single fraction. Do not enter as a decimal.</p>", "showstrings": false, "strings": ["+", "."], "partialcredit": 0.0}, "expectedvariablenames": [], "checkingaccuracy": 0.001, "vsetrange": [0.0, 1.0], "showpreview": true, "vsetrangepoints": 5.0, "checkingtype": "absdiff", "answersimplification": "all, fractionNumbers", "marks": 1.0, "answer": "{a1+b1}/{a1*b1}", "checkvariablenames": false, "type": "jme", "musthave": {"message": "<p>Input as a fraction.</p>", "showstrings": false, "strings": ["/"], "partialcredit": 0.0}}], "type": "gapfill", "marks": 0.0}, {"prompt": "<p>As this question is in practice mode, if you click on the&nbsp;<em>Reveal answers</em>&nbsp;button at the bottom of the screen all the question fields are filled with the correct answers. Also, if available, there will be a full solution given under the heading&nbsp;<em>Advice</em>. Just scroll down to see this. However, there is no Advice available for this question as it is not needed.</p>\n        <p>Finally as you are in practice mode, if you click on the&nbsp;<em>Try another question like this one</em>&nbsp;button at the bottom you will get this question again but with different numbers (usually!), and you can try it again. This is true for all practice mode questions which are randomised.</p>", "type": "information", "marks": 0.0}], "statement": "<p>In this example we show how to enter numbers, either as whole numbers (integers), decimals (rounded to a number of decimal places), or fractions.</p>", "variable_groups": [], "progress": "in-progress", "type": "question", "variables": {"a": {"definition": "random(1..9)", "name": "a"}, "c": {"definition": "random(2..9)", "name": "c"}, "b": {"definition": "random(3..9)", "name": "b"}, "ans1": {"definition": "precround(a1/b1,2)", "name": "ans1"}, "a1": {"definition": "random(2,3,4,5,6,8,9,10,12)", "name": "a1"}, "b1": {"definition": "random(7,11,13)", "name": "b1"}, "tol": {"definition": 0.01, "name": "tol"}}, "metadata": {"notes": "", "description": "<p>Details on inputting numbers into Numbas.</p>", "licence": "Creative Commons Attribution 4.0 International"}, "showQuestionGroupNames": false, "question_groups": [{"name": "", "pickingStrategy": "all-ordered", "pickQuestions": 0, "questions": []}]}, {"name": "Input 3", "extensions": [], "custom_part_types": [], "resources": [], "navigation": {"allowregen": true, "showfrontpage": false, "preventleave": false, "typeendtoleave": false}, "contributors": [{"name": "Christian Lawson-Perfect", "profile_url": "https://numbas.mathcentre.ac.uk/accounts/profile/7/"}], "functions": {}, "tags": ["Numbas", "brackets", "input", "introduction", "numbas", "powers"], "advice": "", "rulesets": {}, "parts": [{"prompt": "<p>Write $e^{\\simplify{{a}x}}$. [[0]]</p>\n      <p>Your input is shown in mathematical notation in a box next to your input so that you can check that you have entered it correctly.</p>\n      <p>Click on <em>Submit part</em> to check your answer.</p>\n      <p>Click on the input field and remove the brackets, then re-submit and see what happens.</p>\n      <p>&nbsp;</p>\n      <p>&nbsp;</p>", "gaps": [{"expectedvariablenames": [], "checkingaccuracy": 1e-05, "vsetrange": [0.0, 0.1], "showpreview": true, "vsetrangepoints": 5.0, "checkingtype": "absdiff", "answersimplification": "all", "marks": 1.0, "answer": "e^({a}*x)", "checkvariablenames": false, "type": "jme"}], "type": "gapfill", "marks": 0.0}, {"prompt": "<p>Input $x^{\\var{c}}x^{\\var{d}}$ as a single power of $x$.</p>\n      <p>For example,&nbsp;you would input&nbsp;$x^{-6}x^{-5}$ as <code>x^(-11)</code>.</p>\n      <p>$x^{\\var{c}}x^{\\var{d}}=\\;$[[0]]</p>", "gaps": [{"expectedvariablenames": [], "checkingaccuracy": 0.001, "vsetrange": [0.0, 1.0], "showpreview": true, "vsetrangepoints": 5.0, "checkingtype": "absdiff", "answersimplification": "all", "marks": 1.0, "answer": "x^({c+d})", "checkvariablenames": false, "type": "jme"}], "type": "gapfill", "marks": 0.0}, {"prompt": "<p>Input $(xy)^{\\var{f}}$ in the form $x^ay^b$ for suitable values of $a$ and $b$.&nbsp;</p>\n      <p>$(xy)^{\\var{f}}=\\;$[[0]]</p>", "gaps": [{"notallowed": {"message": "<p>Input in the form $x^ay^b$ for suitable values of $a$ and $b$.</p>", "showstrings": false, "strings": ["xy", "x*y"], "partialcredit": 0.0}, "expectedvariablenames": [], "checkingaccuracy": 0.001, "vsetrange": [0.0, 1.0], "showpreview": true, "vsetrangepoints": 5.0, "checkingtype": "absdiff", "answersimplification": "all", "marks": 1.0, "answer": "x^{f}*y^{f}", "checkvariablenames": false, "type": "jme"}], "type": "gapfill", "marks": 0.0}], "statement": "<p>In this example we show you how to input powers. It is important that you get this right as many questions ask for such inputs.</p>\n  <p>$a^b$ is input as <code>a^b</code>.</p>\n  <p>But you have to be careful with inputting such expressions as</p>\n  <p>\\[e^{2x},\\;x^{-2},\\;(xy)^2\\]</p>\n  <p><strong>In these cases the exponent must be enclosed in brackets.&nbsp;</strong></p>\n  <table border=\"1\">\n  <tbody>\n    <tr><th>Power</th><th>Correct Input</th><th>Incorrect Input</th><th>Why it's wrong</th></tr>\n  <tr>\n  <td>$e^{2x}$</td>\n  <td><code>e^(2*x)</code></td>\n    <td><code>e^2*x</code></td>\n    <td>The system thinks this is $(e^2) \\cdot x$</td>\n  </tr>\n  <tr>\n  <td>$x^{-2}$</td>\n  <td><code>x^(-2)</code></td>\n    <td><code>x^-2</code></td>\n    <td>This produces an error</td>\n  </tr>\n  <tr>\n  <td>$(xy)^2$</td>\n  <td><code>(x*y)^2</code></td>\n    <td><code>x*y^2</code></td>\n    <td>The system thinks this is $x \\cdot (y^2)$</td>\n  </tr>\n  </tbody>\n  </table>\n  <p>So make sure that you use brackets to properly define your powers. This is a major source of input inaccuracies.</p>\n  <p>To test your input of powers, try the following examples.</p>", "variable_groups": [], "progress": "in-progress", "type": "question", "variables": {"a": {"definition": "random(6..12)*s", "name": "a"}, "s": {"definition": "random(1,-1)", "name": "s"}, "f": {"definition": "random(-5,-4,-3,-2,-1)", "name": "f"}, "c": {"definition": "random(-12..-6)", "name": "c"}, "d": {"definition": "random(-12..-6)", "name": "d"}}, "metadata": {"notes": "", "description": "<p>Information on inputting powers</p>", "licence": "Creative Commons Attribution 4.0 International"}, "showQuestionGroupNames": false, "question_groups": [{"name": "", "pickingStrategy": "all-ordered", "pickQuestions": 0, "questions": []}]}, {"name": "Input 4", "extensions": [], "custom_part_types": [], "resources": [], "navigation": {"allowregen": true, "showfrontpage": false, "preventleave": false, "typeendtoleave": false}, "contributors": [{"name": "Christian Lawson-Perfect", "profile_url": "https://numbas.mathcentre.ac.uk/accounts/profile/7/"}], "functions": {}, "tags": ["Numbas", "algebraic expressions", "input", "introduction", "notation", "numbas", "polynomials", "symbols"], "advice": "", "rulesets": {}, "parts": [{"prompt": "<p>Inputting polynomials such as $3x^2+5x-2$ is easy: just input <code>3*x^2+5*x-2</code>.</p>\n      <p>Input this polynomial: $\\simplify[all]{{a}*x^{b}+{c}*x+{d}}=\\;$[[0]]</p>", "gaps": [{"expectedvariablenames": [], "checkingaccuracy": 0.001, "vsetrange": [0.0, 1.0], "showpreview": true, "vsetrangepoints": 5.0, "checkingtype": "absdiff", "answersimplification": "all", "marks": 1.0, "answer": "{a}*x^{b}+{c}x+{d}", "checkvariablenames": false, "type": "jme"}], "type": "gapfill", "marks": 0.0}, {"prompt": "<p>Now consider this problem.</p>\n      <p>Expand the brackets and input the resulting expression:</p>\n      <p>$\\simplify[all]{(x+{a}y)(x+{c}y)}=\\;$[[0]]</p>\n      <p>(Do not include brackets in your answer.)</p>\n      <p>Two adjacent letters are treated as a single variable: <code>xy</code> is&nbsp;<strong>not</strong> interpreted as the product of $x$ and $y$, $x \\times y$. You must use the multiplication symbol to separate the two variables, i.e. enter <code>x*y</code>. If you don't do this you will often be given a warning that your answer might not have been interpreted as you intended.</p>", "gaps": [{"notallowed": {"message": "<p>Do not include brackets in your answer.</p>", "showstrings": false, "strings": ["("], "partialcredit": 0.0}, "expectedvariablenames": ["x", "y"], "checkingaccuracy": 0.001, "vsetrange": [0.0, 1.0], "showpreview": true, "vsetrangepoints": 5.0, "checkingtype": "absdiff", "answersimplification": "all", "marks": 1.0, "answer": "x^2+{a+c}x*y+{a*c}y^2", "checkvariablenames": true, "type": "jme"}], "type": "gapfill", "marks": 0.0}], "statement": "<p>In this example, we look at how you input algebraic expressions - those involving symbols.</p>\n  <p>The box next to your input shows your answer in mathematical notation and is very important as you can use it to check your answer has been interpreted as you intended.</p>", "variable_groups": [], "progress": "in-progress", "type": "question", "variables": {"a": {"definition": "random(2..9)", "name": "a"}, "s": {"definition": "random(1,-1)", "name": "s"}, "b": {"definition": "random(2..4)", "name": "b"}, "c": {"definition": "s*random(1..9)", "name": "c"}, "d": {"definition": "random(1..9)", "name": "d"}}, "metadata": {"notes": "", "description": "<p>Inputting algebraic expressions into Numbas.</p>", "licence": "Creative Commons Attribution 4.0 International"}, "showQuestionGroupNames": false, "question_groups": [{"name": "", "pickingStrategy": "all-ordered", "pickQuestions": 0, "questions": []}]}, {"name": "Input 5", "extensions": [], "custom_part_types": [], "resources": [], "navigation": {"allowregen": true, "showfrontpage": false, "preventleave": false, "typeendtoleave": false}, "contributors": [{"name": "Christian Lawson-Perfect", "profile_url": "https://numbas.mathcentre.ac.uk/accounts/profile/7/"}], "functions": {}, "tags": ["Numbas", "algebraic input", "brackets", "input", "introduction", "mathematical expressions", "numbas", "ratios"], "advice": "<h4 class=\"partheader\">a)</h4>\n  <p>The correct input is <code>({a}+{b}x)/({c}+{d}y)</code> - the rest are incorrect and you should have chosen those.</p>\n  <h4 class=\"partheader\">b)</h4>\n  <p>A correct input is <code>({b} + {a}y) / ({c} + {d}z)</code>. Also correct is <code>({a}y+{b}) / ({c} + {d}z)</code> etc.</p>\n  <h4 class=\"partheader\">c)</h4>\n  <p>A correct input is <code>({d}z + {b}) / ((x + {a})*(y + {c}))</code>.</p>\n  <p>Note the denominator (the bottom of the ratio) has to have two brackets, i.e. <code>((x + {a})*(y + {c}))</code> as otherwise the expression <code>({d}z + {b}) / (x + {a})*(y + {c})</code> is seen by the system as $\\displaystyle \\left(\\simplify[std]{({d} * z + {b}) / (x + {a})}\\right) (y + \\var{c})$</p>\n  <h4 class=\"partheader\">d)</h4>\n  <p>A correct input is <code>({a} -({b}x + {c})*e ^ ( -{2}x)) / ((x + {2*b})*(y -{3*d}))</code>.</p>\n  ", "rulesets": {"std": ["all", "!collectNumbers"]}, "parts": [{"prompt": "<p>Suppose we wanted to input the expression $\\displaystyle \\frac{\\var{a}+\\var{b}x}{\\var{c}+\\var{d}y}$ into the system.</p>\n      <p>Which of the following input expressions are <em><strong>incorrect</strong></em>?</p>\n      <p>[[0]]</p>\n      <p>Choose the incorrect input(s). (You lose 3 marks if you choose the wrong one!)</p>\n      <p>After you have clicked <em>Submit part</em>, click on <em>Show Feedback</em>&nbsp;and you will be given more detail on your choices.</p>\n      <p>You can click on <em>Reveal answers</em> at the bottom of the screen to see solutions, but it's best to work through&nbsp;these questions yourself. Remember you can always redo the question by clicking on the&nbsp;<em>Try another question like this one</em>&nbsp;button at the bottom of the screen.</p>", "gaps": [{"maxanswers": 0.0, "distractors": ["<code>({a}+{b}x)/({c}+{d}y)</code><br/> This is the correct input, so your choice is wrong!", "<code>{a}+{b}x/({c}+{d}y)</code><br/> Good choice: the system thinks this is $\\simplify[std]{ {a}+{b}x/({c}+{d}y)}$ and not $\\simplify[std]{ ({a}+{b}x)/({c}+{d}y)}$.", "<code>{a}+{b}x/{c}+{d}y</code><br/> Good choice: the system thinks this is $\\simplify[std]{ {a}+{b}x/{c}+{d}y}$ and not $\\simplify[std]{ ({a}+{b}x)/({c}+{d}y)}$.", "<code>({a}+{b}x)/{c}+{d}y</code><br/> Good choice: the system thinks this is $\\simplify[std]{ ({a}+{b}x)/{c}+{d}y}$ and not $\\simplify[std]{ ({a}+{b}x)/({c}+{d}y)}$."], "matrix": [-3.0, 1.0, 1.0, 1.0], "minanswers": 0.0, "shufflechoices": true, "choices": ["<p><code>({a}+{b}x)/({c}+{d}y)</code></p>", "<p><code>{a}+{b}x/({c}+{d}y)</code></p>", "<p><code>{a}+{b}x/{c}+{d}y</code></p>", "<p><code>({a}+{b}x)/{c}+{d}y</code></p>"], "displaytype": "checkbox", "maxmarks": 0.0, "marks": 0.0, "displaycolumns": 1.0, "type": "m_n_2", "minmarks": 0.0}], "type": "gapfill", "marks": 0.0}, {"prompt": "<p>Input the expression $\\displaystyle \\frac{\\var{b}+\\var{a}y}{\\var{d}+\\var{c}z}$. [[0]]</p>", "gaps": [{"expectedvariablenames": [], "checkingaccuracy": 0.001, "vsetrange": [0.0, 1.0], "showpreview": true, "vsetrangepoints": 5.0, "checkingtype": "absdiff", "answersimplification": "std", "marks": 1.0, "answer": "({b}+{a}y)/({d}+{c}z)", "checkvariablenames": false, "type": "jme"}], "type": "gapfill", "marks": 0.0}, {"prompt": "<p>Input the expression $\\displaystyle \\frac {\\var{d} z + \\var{b}} {(x + \\var{a}) (y + \\var{c})}$. [[0]]</p>", "gaps": [{"expectedvariablenames": [], "checkingaccuracy": 0.001, "vsetrange": [0.0, 1.0], "showpreview": true, "vsetrangepoints": 5.0, "checkingtype": "absdiff", "answersimplification": "std", "marks": 1.0, "answer": "({d} * z + {b}) / ((x + {a}) * (y + {c}))", "checkvariablenames": false, "type": "jme"}], "type": "gapfill", "marks": 0.0}, {"prompt": "<p>Input the expression $\\displaystyle \\simplify[std]{({a} -(({b} * x + {c}) * e ^ (( -{2}) * x))) / ((x + {2 * b}) * (y -{3* d}))}$. [[0]]</p>", "gaps": [{"expectedvariablenames": [], "checkingaccuracy": 0.0001, "vsetrange": [0.0, 1.0], "showpreview": true, "vsetrangepoints": 5.0, "checkingtype": "absdiff", "answersimplification": "std", "marks": 1.0, "answer": "({a} -(({b} * x + {c}) * e ^ (( -{2}) * x))) / ((x + {2  b}) * (y -{3* d}))", "checkvariablenames": false, "type": "jme"}], "type": "gapfill", "marks": 0.0}], "statement": "<p>This question concerns ratios of algebraic expressions.</p>\n  <p>By this we mean expressions of the form $\\displaystyle \\frac{p(x)}{q(x)}$ where $p(x)$ and $q(x)$ are algebraic expressions.</p>\n  <p>If you want to input such an expression into the system you <strong>HAVE TO BE CAREFUL AND USE BRACKETS</strong> or mistakes will occur.</p>\n  <p>Once again, the box displaying your input in mathematical notation beside the input boxes in parts <em>a</em>, <em>b</em> and <em>c</em> is very useful as it shows what the system thinks you have entered.</p>", "variable_groups": [], "progress": "in-progress", "type": "question", "variables": {"a": {"definition": "random(2..16#2)", "name": "a"}, "c": {"definition": "random(2..9)", "name": "c"}, "b": {"definition": "random(3..15#2)", "name": "b"}, "d": {"definition": "random(2..9 except [round(b*c/a),c])", "name": "d"}}, "metadata": {"notes": "", "description": "<p>Instructions on inputting ratios of algebraic expressions.</p>", "licence": "Creative Commons Attribution 4.0 International"}, "showQuestionGroupNames": false, "question_groups": [{"name": "", "pickingStrategy": "all-ordered", "pickQuestions": 0, "questions": []}]}]}], "contributors": [{"name": "Jinhua Mathias", "profile_url": "https://numbas.mathcentre.ac.uk/accounts/profile/353/"}], "extensions": [], "custom_part_types": [], "resources": []}