Unit 9 Review 1 (Probability)

Giving a test to a group of students, the grades and gender are summarized in the table.

If one student was chosen at random,

find the probability that the student got an A.

Giving a test to a group of students, the grades and gender are summarized below.

If one student is chosen at random, find the probability that the student did NOT get an "B"

A die is rolled twice. What is the probability of showing a 1 on the first roll and an even number on the second roll?

(Hint: For "and" probabilities of independent events, multiply!)

Lily buys a bag that contains 6 chocolate chip, 6 peanut butter, 6 sugar, and 6 oatmeal cookies.

What is the probability that Lily randomly selects a chocolate chip cookie from the bag, eats it, then reaches back in and randomly selects a peanut butter cookie?

(Hint: Notice the first cookie is not replaced! This is still an "and" problem, so multiply again.)

May buys a bag of cookies that contains 9 chocolate chip, 9 peanut butter, 5 sugar, and 4 oatmeal raisin cookies.

What is the probability that May randomly selects a sugar cookie from the bag, eats it, then randomly selects another sugar cookie? (Notice what changes, and that the cookie isn't replaced. Still an "and" probability!)

Giving a test to a group of students, the grades and gender are summarized in the table.

If one student is chosen at random,

Find the probability that the student was male AND got a "B". (This is the same event, so no multiplying. Just use the table!)

A test was given to a group of students. The grades and gender are summarized in the table.

If one student is chosen at random from those who took the test, find the probability that the student was female GIVEN they got an 'A'. (Hint: the "given" part becomes the denominator!)

A jar contains 2 red marbles numbered 1 to 2 and 8 blue marbles numbered 1 to 8. A marble is drawn at random from the jar. Find the probability the marble is blue or even-numbered. (Remember to add "or" probabilities, and subtract overlapping events or don't count them twice.)

A jar contains 4 red marbles numbered 1 to 4 and 6 blue marbles numbered 1 to 6. A marble is drawn at random from the jar. Find the probability the marble is red or odd-numbered.

A jar contains 10 red marbles numbered 1 to 10 and 6 blue marbles numbered 1 to 6. A marble is drawn at random from the jar. Find the probability the marble is odd-numbered, given that it is red. ("Given" part becomes the denominator!)