Download Probability (part 1)

Day 4 – Probability (Part 1)
Unit 7 - Statistics & Probability
Probability of an Event:
P(event) = # of desired outcome possibilities
Total # of possibilities
Geometric Probability = Shaded area
Total area

Sample Space – list of all possibilities
Deck of Cards: 52 cards → 4 suits (hearts, diamonds, spades, clubs), 2, 3, 4, 5, 6, 7, 8, 9, 10, J, Q, K, A)
A card is chosen from a standard 52-card deck.
Find each theoretical probability.
1. P(club)
2. P(4 of hearts)
3. P(ace)
4. P(five or a seven)
A fair number cube (die) is tossed. Find each probability.
5. P(6 or even)
6. P(even or more than 1)
Use the table to find each probability.
7. P(even or prime)
Characteristics of Camp Counselors
8. P(counselor is a junior)
Grade Level
9. P(counselor is a female)
Male
Female
Junior
18
21
Senior
25
16
10. P(counselor a senior or a male)
11. P(counselor a junior or a female)
Calculate the probability of a point chosen randomly lying in the shaded region. (geometric probability)
12.
5 in
13.
14.
17 ft
4 in
9 ft
1 in 3 in
Square – length is 8 cm
Area of the circle: 34 cm2
Area of the triangle: 68 ft2
Homework – Tuesday December 13, 2011
You randomly select a number from the sample space {5, 7, 9, 11, 13, 15, 17}. Find each theoretical probability.
1. P(less than 13)
2. P(odd)
3. P(multiple of 3 or 5)
A group of five cards are numbered 1–5. You choose one card at random. Find each theoretical probability.
4. P(prime number)
5. P(less than 5)
A bucket contains 15 blue pens, 35 black pens, and 40 red pens. You pick one pen at random. Find each
theoretical probability.
6. P(black pen)
7. P(blue pen or red pen)
8. P(not a blue pen)
9. P(black pen or not a red pen)
A fair number cube is tossed. Find each probability.
10. P(even or 3)
11. P(less than 2 or even)
12. P(prime or 4)
13. You randomly choose a natural number from 1 to 10. What is the probability that you choose a multiple of 2 or 3?
Find each of the following theoretical probabilities.
14. Your classmate rolls a fair number cube. What is the theoretical probability that she will roll a number greater than 4?
15. Shawn rolls a pair of fair number cubes. What is the theoretical probability that he will roll a sum of 3?
16. A box contains 24 green markers, 16 red markers, and 10 blue markers.
a. P(red)
b. P(green or blue)
c. P(not green)
17. A number from 1 to 25 is randomly chosen.
a. What is the probability that the number chosen is a multiple of 2 or 4?
b. What is the probability that the number chosen is a multiple of 2 and 4?
c. What is the probability that the number chosen is a multiple of 2 or 5?
Calculate the probability of a point chosen randomly lying in the shaded region. (geometric probability)
18.
Height of the triangle: 8 in
Area of a triangle = ½ bh
Area of the circle: 32 in2
6 in
19. A garden is 15 ft by 12 ft. Tomatoes fill a 5 foot by 4 foot section of the garden. A squirrel leaps from a tree into
the garden. What is the theoretical probability that the squirrel will land in the tomato section of the garden?
20. The floor in your friend’s house covers 1400 ft2. The floor in her bedroom is 14 ft by 10 ft. What is the probability that
a randomly selected point on the floor of the house is in your friend’s bedroom?