// Numbas version: finer_feedback_settings {"name": "32.d Adding/Subtracting standard form", "extensions": [], "custom_part_types": [], "resources": [], "navigation": {"allowregen": true, "showfrontpage": false, "preventleave": false, "typeendtoleave": false}, "question_groups": [{"pickingStrategy": "all-ordered", "questions": [{"name": "32.d Adding/Subtracting standard form", "tags": ["converting", "scientific notation", "standard form"], "metadata": {"description": "
Convert numbers between 0 and 1 intro standard form/scientific notation.
", "licence": "Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International"}, "statement": "Calculate the following expression and write the answer in standard form.
", "advice": "{advice}
\nUse this link to find some resources which will help you revise this topic.
", "rulesets": {}, "extensions": [], "builtin_constants": {"e": true, "pi,\u03c0": true, "i": true, "j": false}, "constants": [], "variables": {"PowAns": {"name": "PowAns", "group": "Ungrouped variables", "definition": "if(ChangePower, max(Pow1,Pow2)+1, max(Pow1,Pow2))", "description": "", "templateType": "anything", "can_override": false}, "NumAns": {"name": "NumAns", "group": "Ungrouped variables", "definition": "if(ChangePower, AddNums/10, AddNums)", "description": "", "templateType": "anything", "can_override": false}, "Num1": {"name": "Num1", "group": "Ungrouped variables", "definition": "random(1..9#0.1)", "description": "", "templateType": "anything", "can_override": false}, "Num2": {"name": "Num2", "group": "Ungrouped variables", "definition": "random(1..9#0.1)*random(-1,1)", "description": "", "templateType": "anything", "can_override": false}, "Pow1": {"name": "Pow1", "group": "Ungrouped variables", "definition": "random(-12..12)", "description": "", "templateType": "anything", "can_override": false}, "Pow2": {"name": "Pow2", "group": "Ungrouped variables", "definition": "Pow1+PowDiff", "description": "", "templateType": "anything", "can_override": false}, "ChangePower": {"name": "ChangePower", "group": "Ungrouped variables", "definition": "AddNums>=10", "description": "", "templateType": "anything", "can_override": false}, "Advice": {"name": "Advice", "group": "Advice", "definition": "if(PowDiff=0, AdviceSamePow,if(IsPow1Bigger, AdviceNum1Bigger, AdviceNum2Bigger))+if(ChangePower, AdviceChangePower, AdviceNoChange)", "description": "", "templateType": "anything", "can_override": false}, "AdviceChangePower": {"name": "AdviceChangePower", "group": "Advice", "definition": "\"This is not in standard form, we need to divide $\\\\var{AddNums}$ by $10$ and increase the power by $1$ to get a final answer of
\\n\\\\[\\\\var{NumAns}\\\\times 10^\\\\var{PowAns}.\\\\]
\"", "description": "", "templateType": "long string", "can_override": false}, "AdviceNoChange": {"name": "AdviceNoChange", "group": "Advice", "definition": "\"Since this is already in standard form we are done.
\"", "description": "", "templateType": "long string", "can_override": false}, "PowDiff": {"name": "PowDiff", "group": "Ungrouped variables", "definition": "random(-2..2)", "description": "", "templateType": "anything", "can_override": false}, "IsPow1Bigger": {"name": "IsPow1Bigger", "group": "Ungrouped variables", "definition": "PowDiff<0", "description": "", "templateType": "anything", "can_override": false}, "AddNums": {"name": "AddNums", "group": "Ungrouped variables", "definition": "if(IsPow1Bigger, Num1+Num2*10^PowDiff, Num1*10^-PowDiff+Num2)", "description": "", "templateType": "anything", "can_override": false}, "AdviceNum1Bigger": {"name": "AdviceNum1Bigger", "group": "Advice", "definition": "\"To add or subtract numbers in standard form we need both of the powers to be the same. We will write both numbers to the power of $\\\\var{Pow1}$. This gives us
\\\\[\\\\simplify[basic]{{Num1}*10^{Pow1}+{Num2}}\\\\times 10^\\\\var{Pow2}\\\\]
\\\\[=\\\\simplify[basic]{{Num1}*10^{Pow1}+{Num2}}\\\\times10^\\\\var{PowDiff}\\\\times 10^\\\\var{Pow2-PowDiff}\\\\]
\\n\\\\[=\\\\simplify[basic]{{Num1}*10^{Pow1}+{Num2*10^PowDiff}}\\\\times 10^\\\\var{Pow2-PowDiff}.\\\\]
\\nSince both numbers have the same power we can now evaluate them as usual to get
\\n\\\\[\\\\var{AddNums}\\\\times 10^\\\\var{Pow1}.\\\\]
\"", "description": "", "templateType": "long string", "can_override": false}, "AdviceNum2Bigger": {"name": "AdviceNum2Bigger", "group": "Advice", "definition": "\"To add or subtract numbers in standard form we need both of the powers to be the same. We will write both numbers to the power of $\\\\var{Pow2}$. This gives us
\\\\[\\\\simplify[basic]{{Num1}*10^{Pow1}+{Num2}}\\\\times 10^\\\\var{Pow2}\\\\]
\\\\[=\\\\var{Num1}\\\\times10^\\\\var{-PowDiff}\\\\times \\\\simplify[basic]{10^{Pow1+PowDiff}+{Num2}}\\\\times 10^\\\\var{Pow2}\\\\]
\\n\\\\[=\\\\var{Num1*10^-PowDiff}\\\\times \\\\simplify[basic]{10^{Pow1+PowDiff}+{Num2}}\\\\times 10^\\\\var{Pow2}.\\\\]
\\nSince both numbers have the same power we can now evaluate them as usual to get
\\n\\\\[\\\\var{AddNums}\\\\times 10^\\\\var{Pow2}.\\\\]
\"", "description": "", "templateType": "long string", "can_override": false}, "AdviceSamePow": {"name": "AdviceSamePow", "group": "Advice", "definition": "\"To add or subtract numbers in standard form we need both of the powers to be the same. Since both numbers have a power of $\\\\var{Pow1}$ we can simply evaluate them as usual to get
\\\\[\\\\simplify[basic]{{Num1}*10^{Pow1}+{Num2}}\\\\times 10^\\\\var{Pow2}=\\\\var{AddNums}\\\\times 10^\\\\var{Pow1}.\\\\]
$\\simplify[basic]{{Num1}*10^{Pow1}+{Num2}}\\times 10^\\var{Pow2}=$ [[0]]$\\times 10$ [[1]] .
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