Question

6. If 27 is the 5th arithmetic Mean between 7
and 71 then find the number of Arithmetic
Mean terms.​

Answer 1

Answer:

Let A

1

,A

2

,A

n

are n A.Ms inserted between 7 and 71.

So the common difference is d=

n+1

71−7

=

n+1

64

Thus the fifth A.M will be A

5

=7+5d=7+

n+1

64×5

=27 (given)

⇒n+1=

20

64×5

=16⇒n=15

Hence, option 'C' is correct.