Probability 2021 (Period 3 & 7)

A jar contains 2 pink, 6 red, and 4 blue marbles. If you pick one marble without looking, what is the probability that the marble you pick will be red or blue?

• 5/6

• 1/2

• 1/3

• 1/6

Answer explanation

This is a simple event.. no multiplying, there are 10 marbles that are red or blue... out of 12 marbles....10/12 then simplify

A number cube is rolled twice. What is the probability of getting a 6 on the first roll, then a number less than 5 on the second roll?

• 2/3

• 5/36

• 1/9

• 1/36

Answer explanation

Probability of rolling a 6 (1/6) multiplied by probability of rolling a # less than 5 (4/6) , then simplify

Alyssa can choose between 3 sweaters and 4 skirts. If she selects 1 sweater and 1 skirt, how many possible outcomes are in the sample space?

• 7

• 12

• 81

• 10

Answer explanation

multiply 3 by 4

The bar graph shows the results of spinning the spinner 200 times. What is the experimental probability of landing on a 3?

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• 
• 
• 

Answer explanation

A "3" was spun 39 times out of the 200 times the spinner was spun

An ice cream parlor has 6 different flavors. They have 4 toppings and 2 types of cones. How many possible ice cream combinations are there?

• 6

• 48

• 12

• 24

Answer explanation

6 x 4 x 2

You flip a nickel three times.

Find the probability that all flips will land on tails.

• 1/2

• 1/4

• 1/6

• 1/8

Answer explanation

3 events (tails, tails, tails) which is 1/2 x 1/2 x 1/2

Kaylee has 1 red, 3 blue, 2 brown, 5 black, 1 purple, and 4 pairs of pink flip-flops in her closet. Assuming she always replaces them, what is the probability that she will choose a blue pair on Monday and a pink pair on Tuesday?

• 3/8

• 4/75

• 3/64

• 15/32

Answer explanation

Probability of blue (3/16) multiplied by probability of pink (4/16) then simplify

Lucy has the spinner pictured and spins it twice in a row. What is the probability that she lands on blue firstand then on yellow or green?

• 1 / 16

• 1 ⁄ 6

• 1 ⁄ 8

• 3 ⁄ 4

Answer explanation

Probability of blue (1/4) times probability of yellow or green (1/2)

Jamie has 3 raffle tickets. One hundred tickets were sold. Her name was not drawn for the first prize. What is the probability that her name will be drawn for the second prize?

• 1/3

• 1/33

• 3/100

• 2/99

Answer explanation

Her name wasn't drawn first but there was a name drawn.. so now there are only 99 tickets and 3 of them are hers (3/99 then simplify to 1/33)

Probability that is based on repeated trials of an experiment

• Fundamental Counting Principle
• theoretical probability
• experimental probability
• experiment