If p 3 = q 4 = r 5 = s 6 , then the value of log s (pqr) is equal to

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47/10 — Easy Set the common value to $k$ and write each variable as a power of $k$. Then $pqr$ and $s$ are both powers of $k$, so the logarithm is just a ratio of exponents. 1 Express each variable. Let $p^3=q^4=r^5=s^6=k$. $$\begin{aligned} &p=k^{1/3},\quad q=k^{1/4},\quad r=k^{1/5},\quad s=k^{1/6} \end{aligned}$$ 2 Combine for $pqr$. Add the exponents over a common denominator $60$. $$\begin{aligned} &pqr=k^{\frac13+\frac14+\frac15}\ &\frac13+\frac14+\frac15=\frac{20+15+12}{60}=\frac{47}{60}\ &\Righ

CAT 2018 Slot 2 — QA Question 21

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