8
4
a=2, ar=g1,ar2=g2,ar3=g3andar4=32 Now 2 × r4=32⇒r4=16=(2)4=16=(2)4⇒r=2. Then third geometric mean ar2=2×23=16.
Aliter : By formula, G3=2.(322)3/4=2.8=16.
Insert 5 geometric means between 329 and 812.