A phone company collects data on their customers. One set of information the company collects is whether customers use cell phones or
land lines primarily and their ages. The results for 100 customers are
shown on the table below.
under 50
over 50
total
cell
70
5
75
land line
5
20
25
total
75
25
100
What is the conditional relative frequency of customers under 50 who
use cell phones?
75%
93%
80%