// Numbas version: finer_feedback_settings {"name": "NG5 Multiply Fractions", "extensions": [], "custom_part_types": [], "resources": [], "navigation": {"allowregen": true, "showfrontpage": false, "preventleave": false, "typeendtoleave": false}, "question_groups": [{"pickingStrategy": "all-ordered", "questions": [{"name": "NG5 Multiply Fractions", "tags": ["improper fractions", "mixed numbers", "multiplication of fractions", "multiplying fractions", "squared fraction", "taxonomy"], "metadata": {"description": "
Several problems involving the multiplication of fractions, with increasingly difficult examples, including a mixed fraction and a squared fraction. The final part is a word problem.
", "licence": "Creative Commons Attribution 4.0 International"}, "statement": "Evaluate the following multiplication, giving the answer in its simplest form.
", "advice": "\nTo multiply $\\displaystyle\\frac{\\var{a_coprime}}{\\var{c_coprime}}\\times\\frac{\\var{b_coprime}}{\\var{d_coprime}}$, address the numerators and denominators separately.
\nMultiply the numerators across both fractions.
\n$\\var{a_coprime}\\times\\var{b_coprime}=\\var{ab}$,
\nand then multiply the denominators across both fractions.
\n$\\var{c_coprime}\\times\\var{d_coprime}=\\var{cd}$.
\nThe values of the multiplied numerators and denominators will be the numerator and denominator of the new fraction: $\\displaystyle\\frac{\\var{ab}}{\\var{cd}}$.
\nThis answer may need simplifying down, and to do this, find the greatest common divisor in both the numerator and denominator and divide by this number.
\nThe greatest common divisor of $\\var{ab}$ and $\\var{cd}$ is $\\var{gcd}$.
\nBy using $\\var{gcd}$ to cancel down the fraction, the final answer is $\\displaystyle\\simplify{{ab}/{cd}}$.
\n\nUse this link to find some resources which will help you revise this topic.
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