Which of the following are GP? If they are in GP. Write three more terms?
0.4, 0.04, 0.004, ……
Here first term is (a) = 0.4
r1 = 
r2 = 
Common ratios are equal so the given series is in GP.
a4 = a r3 = 0.4×(0.1)3 = 0.0004
a5 = a r4 = 0.4×(0.1)4 = 0.00004
a6 = a r5 = 0.4×(0.1)5 = 0.000004
3