Question

For what value of k will k + 9, 2k -1 and 2k + 7 are the consecutive terms of an A.P.?

Answer 1

18

Explanation:

Since, k + 9, 2k -1 and 2k + 7 are the consecutive terms of an A.P.

Therefore, their common differences would be same.

Hence,

(2k - 1) - (k + 9) = (2k + 7) - (2k - 1)

2k - 1 - k - 9 = 2k + 7 - 2k + 1

k - 10 = 8

k = 8 + 10

k = 18