// Numbas version: finer_feedback_settings
{"name": "Subtract two fractions with the same denominator (some negative numbers).", "extensions": [], "custom_part_types": [], "resources": [], "navigation": {"allowregen": true, "showfrontpage": false, "preventleave": false, "typeendtoleave": false}, "question_groups": [{"pickingStrategy": "all-ordered", "questions": [{"parts": [{"prompt": "<p><fraction><numerator>{a}</numerator><denominator>{d}</denominator></fraction> $\\ -\\ $ <fraction><numerator>{b}</numerator><denominator>{d}</denominator></fraction> $\\ =\\ $ <fraction><numerator>[[0]] $\\ -\\ $ [[1]]</numerator><denominator> [[2]]</denominator></fraction> $\\ =\\ $ <fraction><numerator>[[3]]</numerator><denominator>[[4]]</denominator></fraction>.</p>", "marks": 0, "variableReplacements": [], "gaps": [{"marks": 1, "variableReplacements": [], "correctAnswerStyle": "plain", "mustBeReduced": false, "variableReplacementStrategy": "originalfirst", "scripts": {}, "type": "numberentry", "correctAnswerFraction": false, "notationStyles": ["plain", "en", "si-en"], "allowFractions": false, "showCorrectAnswer": true, "maxValue": "a", "showFeedbackIcon": true, "minValue": "a", "mustBeReducedPC": 0}, {"marks": 1, "variableReplacements": [], "correctAnswerStyle": "plain", "mustBeReduced": false, "variableReplacementStrategy": "originalfirst", "scripts": {}, "type": "numberentry", "correctAnswerFraction": false, "notationStyles": ["plain", "en", "si-en"], "allowFractions": false, "showCorrectAnswer": true, "maxValue": "b", "showFeedbackIcon": true, "minValue": "b", "mustBeReducedPC": 0}, {"marks": 1, "variableReplacements": [], "correctAnswerStyle": "plain", "mustBeReduced": false, "variableReplacementStrategy": "originalfirst", "scripts": {}, "type": "numberentry", "correctAnswerFraction": false, "notationStyles": ["plain", "en", "si-en"], "allowFractions": false, "showCorrectAnswer": true, "maxValue": "d", "showFeedbackIcon": true, "minValue": "d", "mustBeReducedPC": 0}, {"marks": 1, "variableReplacements": [], "correctAnswerStyle": "plain", "mustBeReduced": false, "variableReplacementStrategy": "originalfirst", "scripts": {}, "type": "numberentry", "correctAnswerFraction": false, "notationStyles": ["plain", "en", "si-en"], "allowFractions": false, "showCorrectAnswer": true, "maxValue": "a-b", "showFeedbackIcon": true, "minValue": "a-b", "mustBeReducedPC": 0}, {"marks": 1, "variableReplacements": [], "correctAnswerStyle": "plain", "mustBeReduced": false, "variableReplacementStrategy": "originalfirst", "scripts": {}, "type": "numberentry", "correctAnswerFraction": false, "notationStyles": ["plain", "en", "si-en"], "allowFractions": false, "showCorrectAnswer": true, "maxValue": "d", "showFeedbackIcon": true, "minValue": "d", "mustBeReducedPC": 0}], "showCorrectAnswer": true, "showFeedbackIcon": true, "scripts": {}, "type": "gapfill", "variableReplacementStrategy": "originalfirst"}], "variable_groups": [], "rulesets": {"std": ["all"]}, "functions": {}, "tags": [], "name": "Subtract two fractions with the same denominator (some negative numbers).", "variablesTest": {"maxRuns": 100, "condition": "(a<>1 or b<>-3 or d>2) and (a<0 or b<0) and gcd(a,d)=1 and gcd(b,d)=1"}, "ungrouped_variables": ["a", "b", "d"], "extensions": [], "metadata": {"description": "<p>This question tests a student's ability to subtract one fraction from another with the same denominator. There is at least one negative numerator.</p>", "licence": "Creative Commons Attribution 4.0 International"}, "preamble": {"js": "document.createElement('fraction');\ndocument.createElement('numerator');\ndocument.createElement('denominator');", "css": "fraction {\n  display: inline-block;\n  vertical-align: middle;\n}\nfraction > numerator, fraction > denominator {\n  float: left;\n  width: 100%;\n  text-align: center;\n  line-height: 2.5em;\n}\nfraction > numerator {\n  border-bottom: 1px solid;\n  padding-bottom: 5px;\n}\nfraction > denominator {\n  padding-top: 5px;\n}\nfraction input {\n    line-height: 1em;\n}\n\nfraction .part {\n    margin: 0;\n}\n\n.table-responsive, .fractiontable {\n  display:inline-block;\n}\n.fractiontable {\n  padding: 0; \n  border: 0;\n}\n\n.fractiontable  .tddenom \n{\n text-align: center;\n}\n\n.fractiontable .tdnum \n{\n  border-bottom: 1px solid black; \n  text-align: center;\n}\n\n\n.fractiontable tr {\n    height: 3em;\n}\n"}, "advice": "<p>The correct calculation is $\\dfrac{\\var{a}}{\\var{d}}-\\dfrac{\\var{b}}{\\var{d}}=\\frac{\\boxed{\\var{a}}-\\boxed{\\var{b}}}{\\boxed{\\var{d}}}=\\frac{\\boxed{\\var{a-b}}}{\\boxed{\\var{d}}}$.</p>", "statement": "<p>Subtract one fraction from another using the formula $\\dfrac{a}{b}-\\dfrac{c}{b}=\\frac{\\boxed{a}-\\boxed{c}}{\\boxed{b}}=\\frac{\\boxed{a-c}}{\\boxed{b}}$.</p>\n<p>An example of a correct calculation would be $\\dfrac{1}{2}-\\dfrac{-3}{2}=\\frac{\\boxed{1}-\\boxed{-3}}{\\boxed{2}}=\\frac{\\boxed{2}}{\\boxed{2}}$.</p>\n<p>Note the final fraction should be left as it is and should not be entered in lowest form (if this is different).</p>", "variables": {"d": {"templateType": "anything", "name": "d", "description": "<p>The common denominator.</p>", "definition": "random(2..99)", "group": "Ungrouped variables"}, "b": {"templateType": "anything", "name": "b", "description": "<p>Numerator of the second fraction.</p>", "definition": "random(-99..99 except 0)", "group": "Ungrouped variables"}, "a": {"templateType": "anything", "name": "a", "description": "<p>Numerator of the first fraction.</p>", "definition": "random(-99..99 except 0)", "group": "Ungrouped variables"}}, "type": "question", "contributors": [{"name": "Anthony Brown", "profile_url": "https://numbas.mathcentre.ac.uk/accounts/profile/799/"}]}]}], "contributors": [{"name": "Anthony Brown", "profile_url": "https://numbas.mathcentre.ac.uk/accounts/profile/799/"}]}