Competition problem — Algebra — Maths Olympiad Prep

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Algebra Difficulty 1.5 Junior Find the answer

An integer $n$ is decreased by 2 and then multiplied by 5. If the result is 85, what is the value of $n$ ?

Your answer

A number or a short expression. Spacing and $ signs are ignored.

Solution

We undo each of the operations in reverse order. The final result, 85, was obtained by multiplying a number by 5. This number was $85 \div 5=17$ . The number 17 was obtained by decreasing $n$ by 2. Thus, $n=17+2=19$ .

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