Question

inser A.M.s between 7 and 71 in such a way that the 5th A.M. is 27. find the number of A.M.s.

Answer 1

Here , a=7 , c=71  

5th A.M. is = 27

         a+5d=27         [ d= common difference]

         7+5d=27

              5d=20

                 d=4

 Now we have, d=(c-a)/(n+1)  

                           4=(71-7)/(n+1)

                   4(n+1)=64

                           4n =60

                             n=15

Therefor number of A.M. is 15