Suppose the percentage of females who support a

7. Suppose the percentage of females who support a casino in Columbus is 55%. If
supporting a casino in Columbus is independent of gender, what percentage of
males support a casino in Columbus?
a. 55%
b. 45%
c. Unknown
8. Suppose the chance that a randomly chosen OSU student owns a dog is 10%, and
the chance that a randomly chosen OSU student owns a cat is 15%. Suppose we
know that 25% of all cat owners at OSU also own dogs. What is the chance that
any randomly chosen student at OSU owns a cat and a dog?
9. Suppose 20% of all women aged 30-50 in the U.S. subscribe to Oprah’s
magazine, and 3% of all men aged 30-50 in the U.S. subscribe to Oprah’s
magazine. From this info we can say that subscribing to Oprah’s magazine is
independent of gender.
a. TRUE b. FALSE because P(subscribe|male) not equal to
P(subscribe|female)
10. Suppose the following two-way table shows data on people’s opinion of a new
candidate for president, by gender. According to these results, gender and opinion
of the new candidate are independent.
a. TRUE b. FALSE
Support Oppose
Male 60 40
Female 60 40
2

11. Suppose X is a continuous random variable and the possible values of X are all
real numbers between 0 and 10. Then the probability that X equals 5 is:
12. Suppose X and Y are independent. The variance of X – Y equals the -1 times the
variance of Y – X.
a. YES b. NO
13. Suppose X and Y are independent, and they both have the same standard
deviation of 2. Then the standard deviation of X + Y is 4.
a. YES b. NO