Question

If k + 6, 2k + 6 and 5k − 2 are in A.P., then the value of k is ______.

Options

• 4

• 5

• 6

• 8

Answer 1

If k + 6, 2k + 6 and 5k − 2 are in A.P., then the value of k is 4.

Explanation:

a = k + 6

b = 2k + 6

c = 5k − 2

2b = a + c

2(2k + 6) = (k + 6) + (5k − 2)

4k + 12 = 6k + 4

12 − 4 = 6k − 4k

8 = 2k

k = `8/2`

k = 4