Question

Following are APs or not? If they form an A.P. find the common difference d and write three more terms: 

0.2, 0.22, 0.222, 0.2222 ….

Answer 1

0.2, 0.22, 0.222, 0.2222 ….

It can be observed that

a₂ − a₁ = 0.22 − 0.2 = 0.02

a₃ − a₂ = 0.222 − 0.22 = 0.002

a₄ − a₃ = 0.2222 − 0.222 = 0.0002

i.e., a_k+1 − a_k is not the same every time.

Therefore, the given numbers are not in A.P.