Question

If the 3rD
7th and 12th terms of an AP are three consecutive terms of a GP find the common ratio of GP


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Answer 1

Step-by-step explanation:

3rd term of AP-- a+2d

7th term of AP-- a+6d

12th term of AP-- a+11d

The above terms are in GP

(a+2d)(a+11d)=(a+6d)^2

a^2+13ad+22d^2=a^2+12ad+36d^2

ad=14d^2

a=14d

Common ratio=(a+2d)/(a+6d)

=16d/20d

=4/5