A person with type O-negative blood can donate blood to anyone who needs it,regardless of blood type.About 7% of the U.S.population has type O-negative blood.Your workplace is hosting a blood drive this afternoon.How many potential donors do you expect they will have to examine in order to get 3 units of type O-negative blood?
A)2187 people
B)43 people
C)21 people
D)343 people
E)0.21 people

Question

Quizplus · Accepted Answer

Since 7% of the population has type O-negative blood, we can assume that approximately 7% of the potential donors at the blood drive will have this blood type. We need 3 units, so we need to examine 3/0.07 or approximately 42.9 people. Therefore, the closest option is B, which is 43 people.

A Person with Type O-Negative Blood Can Donate Blood to Anyone