Question

What’s the common ratio of this sequence?
3, 21, 147

Answer 1

r = 7

Explanation:

The common ratio r of a geometric sequence is

r =
`(a_(2) )/(a_(1) )` =
`(a_(3) )/(a_(2) )`, that is

r =
`(21)/(3)` =
`(147)/(21)` = 7