Sheet # 242
Name: _____________________ Date_____________
Show your work.
1) There are 10 balls in a bag. Half of them are black. Half of them are blue. What is the probability of pulling out a blue ball?
2) Danny and Charlie have a cup filled with seven orange marbles and eight blue marbles. Danny says his chances of pulling out an orange marble from the cup are 7 in 15. Charlie says the chances of pulling out an orange marble are 1 in 7. Who is correct and why?
3) A bag contains one blue marble, one red marble, and one green marble. You reach in the bag and pull out a red marble. If you keep the marble and then reach in again, what are your chances of pulling out a green marble?
4) A spinner is divided into three parts: 1/2 is labeled red, 1/4 is labeled blue, and 1/4 is labeled green. Is the spinner fair? What is the probability of NOT getting blue?
Answers for sheet # 242
1) Number of black balls = 5
Number of blue balls = 5
Probability of picking up a blue ball = 5/10 = 1/2
2) Danny is correct.
The total number of marbles = 15.
7 marbles are orange
Probability of getting an orange marble = 7/15
3) After removing the red ball, only two balls are left in the bag.
Probability getting a green ball = 1/2
4) It is not a fair spinner as there is more red area than blue or green area.
Probability of NOT getting blue = Probability of getting red + probability of getting green
= (1/2) + (1/4)
= 3/4