4. At the Old Fort Boise Days Car Show there were 15 Pontiacs, 18 Chevrolets, 12 Fords ,and 5 Ramblers. What was the ratio of Ramblers to the total number of cars in the Car Show?
a.
5:45
c.
1:10
b.
10:1
d.
50:5

Amanufacturer knows that their items have a normally distributed lifespan, with a mean if 9.1 years, and standard deviation of 2.9 years. if you randomly purchase one item, what is the probability it will last longer than 10 years?