Competition problem — Algebra — Maths Olympiad Prep

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Algebra Difficulty 1.7 Junior Find the answer

Which of the following divisions is not equal to a whole number: $\frac{60}{12}$ , $\frac{60}{8}$ , $\frac{60}{5}$ , $\frac{60}{4}$ , $\frac{60}{3}$ ?

Your answer

A number or a short expression. Fractions can be typed as 3/2, and spacing doesn't matter.

Solution

Since $\frac{60}{8}=60 \div 8=7.5$ , then this choice is not equal to a whole number. Note as well that $\frac{60}{12}=5, \frac{60}{5}=12, \frac{60}{4}=15$ , and $\frac{60}{3}=20$ are all whole numbers.

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