// Numbas version: finer_feedback_settings {"name": "19.e. Finding all factors of a number", "extensions": [], "custom_part_types": [], "resources": [], "navigation": {"allowregen": true, "showfrontpage": false, "preventleave": false, "typeendtoleave": false}, "question_groups": [{"pickingStrategy": "all-ordered", "questions": [{"name": "19.e. Finding all factors of a number", "tags": [], "metadata": {"description": "

Prime factor decomposition starting steps.

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Provide all the factors of $\\var{Number}$.

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For any number $n$ we know 1 and $n$ will always be factors. We will work out the rest of the factors by testing which numbers divide {Number}.

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First try dividing by 2, if this does not work then try 3, then 4 and so on. (In fact, to find the first factor you only need to check the prime numbers 2,3,5,7,...).

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After 1, the first number which divides {Number} is {Factors[1]}. This means that both {Factors[1]} and {Number/Factors[1]} are factors. We can now speed up the process of looking for factors of {Number} by looking for factors of {Number/Factors[1]} instead. Make sure to remember that if $x$ is a factor of {Number/Factors[1]} then both $x$ and $\\var{Factors[1]}\\times x$ are factors of {Number}!

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We only need to look for factors up to $\\sqrt{\\var{Number}}$. Once you have done this you should have the full list of factors {AnswersAsString}.

\n

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Use this link to find some resources which will help you revise this topic.

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All numbers less than 119 have 12 or fewer factors so can't increase this range without increasing the number of options

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Leave boxes empty if there is not enough factors.

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