19) 3
P(A and B)
3
P(BA)
20
==
P(A) = ?
5

A)1/4
B)3/4
C)9/200
D)5/8

When rates are expressed as a quantity of 1, such as 2 feet per second or 5 miles per hour, they are called unit rates. if you have a multiple-unit rate such as 120 students for every 3 buses, and want to find the single-unit rate, write a ratio equal to the multiple-unit rate with 1 as the second term.