Question
If the first term of an A.P. is 3 and the sum of its first 25 terms is equal to the sum of its next 15 terms, then the common difference of this A.P. is :(a) $\frac{1}{6}$(b) $\frac{1}{5}$(c) $\frac{1}{4}$(d) $\frac{1}{7}$
Step 1
Step 1: The sum of the first n terms of an arithmetic progression can be given by the formula $S_n = \frac{n}{2}[2a + (n-1)d]$, where $a$ is the first term and $d$ is the common difference. Show more…
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