// Numbas version: exam_results_page_options {"name": "Percentages: Finding original values 1", "extensions": [], "custom_part_types": [], "resources": [], "navigation": {"allowregen": true, "showfrontpage": false, "preventleave": false, "typeendtoleave": false}, "question_groups": [{"pickingStrategy": "all-ordered", "questions": [{"name": "Percentages: Finding original values 1", "tags": [], "metadata": {"description": "

Calculating the original amount when told that $p\\%$ is $x$. The value given and the original values are both integers.

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If we know that $\\var{p}\\%$ of a value is $\\var{new}$, it can help to think of the original value as $100\\%$, and then calculate how many times $\\var{p} \\%$ goes into $100 \\%$.

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Since $\\var{p} \\%$ goes into $100 \\%$ $\\var{100/p}$ times ($100 \\div \\var{p} = \\var{100/p}$), this tells us that $\\var{new}$ will also go into the original value $\\var{100/p}$ times.

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Therefore,

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\\[ \\begin{split} \\text{Original value } &\\,= \\var{new} \\times \\var{100/p} \\\\ &\\,= \\var{ans} . \\end{split} \\]

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Given that {p}% of a value is {new}, what is the original value?

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