CEMC Pascal

Algebra Difficulty 1.9 Junior Find the answer

If $3 \times 3 \times 5 \times 5 \times 7 \times 9 = 3 \times 3 \times 7 \times n \times n$ , what is a possible value of $n$ ?

Your answer

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

Solution

Since $3 \times 3 \times 5 \times 5 \times 7 \times 9 = 3 \times 3 \times 7 \times n \times n$ , then $n \times n = \frac{3 \times 3 \times 5 \times 5 \times 7 \times 9}{3 \times 3 \times 7} = 5 \times 5 \times 9 = 5 \times 5 \times 3 \times 3$ . Since $n \times n = 5 \times 5 \times 3 \times 3$ , then a possible value for $n$ is $n = 5 \times 3 = 15$ .

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