Question

First, second and seventh terms of an A.P.(all the terms are distinct), whose sum is $93$, are in G.P. fourth term of this G.P. is

• A. $21$
• B. $31$
• C. $75$
• D. $375$

Answer 1

The correct option is D $375$

First term $=a$, 2nd term$=a+d$, 7th term $=a+6d$

Sum $=93$

$a+a+d+a+6d=93$

$3a+7d=93$

Thus term in GP So

$\frac{a+d}{a}=\frac{a+6d}{a+d}$

Solving $d=4a$

$a=3,d=12$

Therefore the A.P is $3,15,27,....$

and G.P is $3,15,75,375$

4th term $=375$