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Algebra Difficulty 2.1 Junior Find the answer

If (pq)(qr)(rp)=16(pq)(qr)(rp) = 16, what is a possible value for pqrpqr?

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

Solution

Since (pq)(qr)(rp)=16(pq)(qr)(rp) = 16, then pqqrrp=16pqqrrp = 16 or p2q2r2=16p^2q^2r^2 = 16. Thus, (pqr)2=16(pqr)^2 = 16 and so pqr=±4pqr = \pm 4. Using the given answers, pqrpqr is positive and so pqr=4pqr = 4.

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