At a local high school, enrollment in the drama club increases by 5% each year. What is the common ratio in this situation?

a) 0.05

b) 0.95

c) 1.05

d) 1.95

The common ratio is 1.05.

The common ratio is what you are multiplying a previous term by to get the next term in a geometric sequence.

If you want to increase a number by 5%, you need to multiply by

(1 + 5%) = (1 + 0.05) = 1.05

to achieve that.