# Probability

1. Last fall, a gardener planted 65 iris bulbs. She found that only 56 of the bulbs bloomed in the spring.

a) Find the empirical probability that an iris bulb of this type will bloom

b) How many of the bulbs should she plant next fall if she would like at least 92 to bloom?

2. The last 40 violent crimes committed in Sconeville were 2 homicides, 25 robberies, and 13 assaults. What is the empirical probability that the next violent crime committed in Sconeville will be a robbery?

3. One card is selected at random from a standard 52-card deck of playing cards. Find the probability that the card selected is not a spade.

4. The odds against WildHorse winning the third race are 11:2. If Molly places a $4 bet on WildHorse to win and WildHorse wins, find Molly's net winnings

A) $5.50 B) $44 C) $16.50 D) $11 E) $22

5. 500 raffle tickets are sold at $2 each. One grand prize of $100 and two consolation prizes of $50 will be awarded. Find Jake's expectation if he purchases one ticket.

A) -$0.40 B) -$1.20 C) -$1.60 D) $7.75 E) $0.80

6. An independent television station airs a movie-of-the-week every Wednesday. Their market research shows that their horror movies are viewed by an average of 2600 people, their comedies are viewed by 4200 people, and their dramas are viewed by 8000 people. The station buys a package of 50 movies, consisting of 5 horror movies, 20 comedies, and 25 dramas. The movies will be shown one per week for 50 weeks. Find the expected number of viewers on a given movie.

A. 5940 B. 5560 C. 4360 D. 6920 D. 5400

7. How many different four-digit numbers can be formed from the digits 0 through 9 if the first digit must be even and cannot be zero?

8. A box of chocolates contains 20 identically shaped chocolates. Five of them are filled with jelly, three are filled with caramel, and twelve are filled with nuts. What is the probability that one chocolate chosen at random is filled with jelly, caramel, or nuts?

9. A couple plans to have exactly three children.

(a) Construct a tree diagram and list the sample space.

(b) Find the probability that the family has at least two girls.

10. (A card is selected from a deck of 52 playing cards. Find the probability of selecting

a) a diamond given the card is black

b) a queen given the card is a picture card.

#### Solution Summary

Ten probability problems are solved. The solution is detailed and well presented.