Compound and Conditional Probabililities

A bag contains 5 blue marbles, 4 red marbles, and 3 orange marbles. Mrs. Cox picks one without looking, replaces it and picks another one. What is the probability that she picks two that are not orange?

• $\frac{9}{16}$

• $\frac{3}{4}$
  

• $\frac{9}{144}$
  

• $\frac{5}{16}$
  

You have a bag of 17 marbles. 4 are blue, 6 are green, 2 are red, and the others are yellow. What is the probability of drawing a green marble, putting it aside, and then drawing another green marble?

• $\frac{30}{272}$

• $\frac{30}{289}$
  

• $\frac{36}{272}$
  

• $\frac{36}{289}$

In the game that Tony is playing, there is a  $\frac{1}{8}$   chance the spinner will land on red and a  $\frac{3}{8}$   chance that the spinner will land on yellow. What is the probability that Tony will NOT spin red, then will spin red?

• $\frac{7}{64}$

• $\frac{7}{16}$

• $\frac{3}{64}$
  

• $\frac{15}{64}$

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?

• $\frac{2}{3}$

• $\frac{5}{36}$
  

• $\frac{4}{36}$
  

• $\frac{1}{36}$
  

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 spinnerandpicks a red marble out of the bag?

• $\frac{2}{32}$

• $\frac{16}{32}$

• $\frac{8}{32}$
  

• $\frac{4}{32}$
  

You have a bag of 17 marbles. Four are blue, 6 are green, 2 are red, and the others are yellow. What is the probability of drawing a red marble, putting it aside, and then drawing a green marble?

• $\frac{12}{272}$

• $\frac{30}{272}$

• $\frac{36}{272}$
  

• $\frac{10}{272}$

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?

• $\frac{1}{3}$

• $\frac{3}{99}$
  

• $\frac{3}{100}$
  

• $\frac{2}{99}$
  

You roll a six sided die. What is the probability of rolling an even number three times in a row?

• $\frac{3}{100}$

• $\frac{108}{216}$
  

• $\frac{3}{6}$

• $\frac{27}{216}$
  

A chorus has 50 girls and 35 boys. If two are chosen at random to sing a duet, what is the probability that both will be boys? HINT: You can not have the same person twice in a duet

• $\frac{1190}{7140}$

• $\frac{1225}{7140}$
  

• $\frac{1500}{7225}$
  

• $\frac{1190}{7225}$
  

A quiz contains 5 true or false questions. If you forgot to study and do not know the answer to them and guess, what is the probability of getting them all right? HINT: What is the probability of getting a True or False question correct on a test

• $\frac{1}{5}$

• $\frac{1}{32}$
  

• $\frac{5}{32}$
  

• $\frac{1}{2}$