Independent Probability Review

Independent probability happens when the probability of the first event does not affect the probability of the second event.

• True

• False

A coin and a number cube with the numbers 1 through 6 are tossed. What is the probability of the coin showing tails and the number cube showing the number 3? 

• 1/12

• 1/4

• 1/8

• 1/2

Ricardo has the spinner pictured here and a bag of marbles filled with 2 red marbles, 3 green marbles, and 3 blue marbles. What is the probability that Ricardo spins red on the spinner and picks a red marble out of the bag?

• 1 ⁄ 16

• 1 ⁄ 2

• 1 ⁄ 4

• 1 ⁄ 8

Tom will randomly select from a treat bag containing 6 lollipops and 4 gum balls. What is the probability that Tom will select a lollipop, replace it, and then select a gum ball.

• 1/24

• 1/90

• 6/25

• 1/10

Ten cards numbered 1-10 are placed in a hat. What is the probability of randomly drawing a card with an even number then a card with a number five or greater if the first card is replaced?

• 1/4

• 2/3

• 3/10

• 3/5

What is the probability that Tom will get a lollipop, replace it, then draw a gumball? The treat bag containing 6 lollipops and 4 gum balls

• 1/24

• 1/90

• 6/25

• 1/10

There are six nickels and seven dimes in your pocket. You randomly pick a coin out of your pocket and then return it to your pocket. Then you randomly pick another coin. What is the probability that both times the coin is a nickel?

• 6/13

• 2/7

• 5/16

• 3/19

• 36/169

A marble bag contains 3 red marbles, 4 gray marbles, 6 white marbles, and 5 black marbles. What is the probability of randomly drawing a red marble and then a gray marble if the first marble is replaced?

• 1/9

• 1/27

• 1/6

• 2/9

Marietta picks a candle from the bunch, replaces it, and then selects one again. What are the chances that she selects a green both times?

• 1/144

• 1/12

• 1/36

• 2/24

• 2/12

Match each to its probability.

• 12/60

• P(keyboard | 7th grade)

• 12/40

• P(drums and 8th grade)

• 12/180

• P(drums or 8th grade)

• 40/180

• P(keyboard)

• 81/180

• P(7th grade | keyboard)