// Numbas version: exam_results_page_options {"name": "Add two fractions with different denominators", "extensions": [], "custom_part_types": [], "resources": [], "navigation": {"allowregen": true, "showfrontpage": false, "preventleave": false, "typeendtoleave": false}, "question_groups": [{"pickingStrategy": "all-ordered", "questions": [{"metadata": {"licence": "Creative Commons Attribution 4.0 International", "description": "

This question tests a student's ability to add two fractions with different denominators.

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Numerator of the first fraction.

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This is the denominator of the first fraction.

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This is the denominator of the second fraction.

", "group": "Ungrouped variables", "name": "d"}, "c": {"definition": "random(1..99)", "templateType": "anything", "description": "

This is the numerator of the second fraction.

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The correct calculation is $\\dfrac{\\var{a}}{\\var{b}}+\\dfrac{\\var{c}}{\\var{d}}=\\frac{\\boxed{\\var{a*d}}+\\boxed{\\var{b*c}}}{\\boxed{\\var{b*d}}}=\\frac{\\boxed{\\var{a*d+b*c}}}{\\boxed{\\var{b*d}}}$.

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{a}{b} $\\ +\\ $ {c}{d} $\\ =\\ $ [[0]] $\\ +\\ $ [[1]] [[2]] $\\ =\\ $ [[3]][[4]].

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Add the following fractions using the formula $\\dfrac{a}{b}+\\dfrac{c}{d}=\\frac{\\boxed{ad}+\\boxed{bc}}{\\boxed{bd}}=\\frac{\\boxed{ad+bc}}{\\boxed{bd}}$.

\n

An example of a correct calculation would be $\\dfrac{1}{2}+\\dfrac{3}{4}=\\frac{\\boxed{4}+\\boxed{6}}{\\boxed{8}}=\\frac{\\boxed{10}}{\\boxed{8}}$.

\n

Note that in the intermediate stage, you have to use the denominator $bd$ to be marked correct, you should not use a smaller common denominator (if one exists). Also note the final fraction should be left as it is and should not be entered in lowest form (if this is different).

", "name": "Add two fractions with different denominators", "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/"}]}