Question
If the $(m+1)$ th, $(n+1)$ th and $(r+1)$ th terms of an A.P. are in G.P. and $m, n, r$ are in H.P., then the ratio of the first term of the A.P. to its common difference is(A) $\frac{n}{3}$(B) $-\frac{n}{3}$(C) $\frac{n}{2}$(D) $-\frac{n}{2}$
Step 1
P. be $a$ and the common difference be $d$. Then the $(m+1)$ th, $(n+1)$ th and $(r+1)$ th terms of the A.P. are $a+md$, $a+nd$ and $a+rd$ respectively. Show more…
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