If \(p, q\) and \(r\) are in AP, then what is \(p^3+3pr(p+r)+r^3\) equal to?
\(8q^3\)
Since \(p^3+3pr(p+r)+r^3 = (p+r)^3\) (using \((p+r)^3 = p^3+r^3+3pr(p+r)\)), and \(p,q,r\) in AP gives \(p+r=2q\), the expression equals \((2q)^3 = 8q^3\).
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Select the correct answer using the code given below:How many two-digit numbers are divisible by 4?
