// 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}, "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.

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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} $\\ =\\$ [] $\\ +\\$ [] [] $\\ =\\$ [][].

Add the following fractions using the formula $\\dfrac{a}{b}+\\dfrac{c}{d}=\\frac{\\boxed{ad}+\\boxed{bc}}{\\boxed{bd}}=\\frac{\\boxed{ad+bc}}{\\boxed{bd}}$.
An example of a correct calculation would be $\\dfrac{1}{2}+\\dfrac{3}{4}=\\frac{\\boxed{4}+\\boxed{6}}{\\boxed{8}}=\\frac{\\boxed{10}}{\\boxed{8}}$.
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).