Page 139 - Probability Demystified

128 CHAPTER 7 The Binomial Distribution

8. A survey found that 30% of all Americans have eaten pizza for break-
fast. If 500 people are selected at random, the mean number of people
who have eaten pizza for breakfast is
a. 100
b. 150
c. 200
d. 230
9. A survey found that 10% of older Americans have given up driving.
If a sample of 1000 Americans is taken, the standard deviation of the
sample is

a. 10
b. 8.42
c. 9.49
d. 5
10. A survey found that 50% of adults get the daily news from radio. If a
sample of 64 adults is selected, the approximate range of the number
of people who get their news from the radio is

a. 24 and 40
b. 30 and 34
c. 28 and 32
d. 26 and 36

Probability Sidelight

PASCAL’S TRIANGLE

Blaise Pascal (1623–1662) was a French mathematician and philosopher. He
made many contributions to mathematics in areas of number theory, geometry,
and probability. He is credited along with Fermat for the beginnings of the
formal study of probability. He is given credit for developing a triangular array
of numbers known as Pascal’s triangle, shown here.