Henrico Math 8 Probability

I see three doors, one only opens out, another only open in, and the other opens both ways. What is the probability that I choose one that opens out?

• 1/9

• 1/3

• 2/3

• 1/1

I flip a coin twice. What is the probability I get heads twice?

• .25

• .5

• 75%

• 100%

Lynette made the following diagram. Which list shows all the possible outcomes, according to her tree diagram?

• C, O, G

• A, B, C, O, G

• AB, COG

• AC, AO, AG, BC, BO, BG

A jar has 24 green lollipops, 13 blue lollipops, 28 red lollipops and 15 purple lollipops. If Michelle picks two lollipops at random, what is the probability that Michelle will select a red lollipop and then a purple lollipop?

• 21/320

• 28/80

• 1/2

• 15/80

A box contains 20 balls: 10 are yellow, 6 are red and 4 are black. What is the probability of selecting a yellow ball and then a red ball?

• 1/2

• 3/10

• 3/20

• 10/20

What is the probability of NOT rolling an EVEN number on a 6-sided number cube?

• 1 in 2

• 1 in 3

• 1 in 6

• 5 in 6

Tech Group Corporation accepts 1 of every 20 applicants. What is the probability of NOT being accepted for a job at Tech Group?

• 1%

• 5%

• 19%

• 95%

A spinner has 3 equal sections that are red, blue, and white. What is the probability of NOT landing on a red?

• 1/4

• 2/3

• 1/5

• 1/2

A bag contains 2 silver coins, 2 gold coins, 6 copper coins, and 5 brass coins. A coin is chosen without looking. What is the probability that it will be gold?

• 11/15

• 6/15

• 4/15

• 2/15

At Mr. Gonzalez's convenience store, the probability of a student purchasing a cola is 11/20. About how many students would purchase a cola if 280 students come in during one day?

• 130 students

• 178 students

• 126 students

• 154 students