Name: Date: Unit 11: Probability & Statistics Homework 3: Conditional Probability Bell: ** This is a 2-page document! ** Use for questions 1-2: A bucket contains 50 lottery balls numbered 1-50. One is drawn at random. Find each probability. 1. P(multiple of 6 | 2-digit number) 2. P(at least 20 | prime number) 3. Marti rolls two dice. What is the probability that the sum of the dice is 7, given that the first die is showing a 2? 4. Blake randomly chose a letter from alphabet. What is the probability that this letter has at least one line of symmetry, given that it is a consonant? 5. A card is randomly selected from a standard deck of playing cards. Find the probability that it is a face card, given that a black card is drawn. 6. A month of the year is randomly chosen. Find the probability that it has no more than 30 days, given that it starts with the letter A. 7. P(black | A) Use for 7-9: The wheel below is spun. Find each probability. BA D 8. P(C | white) A 9. P(black | B or E) C B 10. Out of the 125 children at summer camp, 45 signed up for swimming and 38 signed up for arts and crafts. Twelve students who signed up for swimming also signed up for arts and crafts. If a child is randomly selected, what is the probability that they are signed up for swimming, if it is known that they did not sign up for arts and crafts? 11. Out of the 56 players on the football team, 24 are on honor roll and 18 have perfect attendance. Seven who are on honor roll also have perfect attendance. If a player is chosen at random, what is the probability that they are on honor roll, if it is known that they also have perfect attendance? AS rar E B 100% or your m Directions: Find each probability using the table. 12. The table below shows the number of a) P(a student with a part-time job without a car) students that do or do not have their own car and whether they have part time jobs. b) P(no car | does not have a part-time job) Part Time Job Yes No Yes 78 18 8 c) P(part-time job | car) No 30 24 a) P(a 3rd class survivor) 13. The table below shows the fate of the first, second, and third class passengers on the Titanic. b) P(1 class | died) Survived Died 1st Class 199 120 2nd Class 117 155 c) P(survived | 2nd class) 3rd Class 172 537 d) P(1st or 3rd class | survived) 14. The table below represents the GPA of a group of undergrad students and whether or not they will be attending grad school. Find the joint relative and marginal relative frequencies. Attending Grad School Total Yes No Attending Grad School Yes No 23.0 23.0 96 18 <3.0 <3.0 32 54 Total If a student is chosen at random, find each probability: a) P(not attending grad school) b) P(< 3.0 GPA and not attending grad school) c) P(not attending grad school | 23.0 GPA) d) P(< 3.0 GPA | attending grad school) Gina Wilson (All Things Algebra), 2016