Probability and Statistics

How does the theoretical probability of the event “flip heads” change when a coin is flipped more times in an experiment?

• If a head is flipped, the theoretical probability will increase.

• If a tail is flipped, the theoretical probability will increase.

• If a tail is flipped, the theoretical probability will decrease.

• The theoretical probability will not change.

Stacy uses a spinner with six equal sections numbered 2, 2, 3, 4, 5, and 6 to play a game.

Select the three true statements about this game.

• The probability of the pointer landing on an even-numbered section is 66.67%.

• It is impossible that the pointer will land on 1.

• It is less likely that the pointer will land on an odd-numbered section.

• It is certain that the pointer will land on a number less than 6.

• The spinner is fair.

Tags

CCSS.7.SP.C.5

Stacy uses a spinner with six equal sections numbered 2, 2, 3, 4, 5, and 6 to play a game.

Stacy spins the pointer 120 times and records the results. The pointer lands 30 times on a section numbered 2, 19 times on 3, 25 times on 4, 29 times on 5, and 17 times on 6. A winning spin is a 2. Find the theoretical and experimental probabilities of winning, and compare the two.

• The theoretical and experimental probabilities are always the same.

• There is not enough information to find the theoretical probability.

• Theoretical Probability, 33.3% > 25%

• Experimental Probability , 33.3% > 25%

Rachel plays a game by rolling two number cubes with sides numbered 1 through 6. To win the game, the sum of the numbers facing up must be 11. What is the probability that Rachel will win the game?

• P(sum of 11) = 2/6

• P(sum of 11) = 2/12

• P(sum of 11) = 2/24

• P(sum of 11) = 2/36

Tags

CCSS.7.SP.C.7B

Brianna has a bag of marbles that are all the same size. Of all the marbles in the bag, there are 6 red, 7 white, 3 black, and 4 green marbles.

Ryan asks 80 people to choose a marble, note the color, and replace the marble in Brianna’s bag. The results of the random marble selections in this experiment are: 34 red, 18 white, 9 black, and 19 green marbles. How does the theoretical probability compare with the experimental probability of drawing a white marble?

• Experimental Probability, 35% > 22.5%

• Experimental Probability, 90% > 10%

• Theoretical Probability, 35% > 22.5%

• Theoretical Probability 90% > 10%

Jewel spins the pointer of a spinner. The spinner has 7 equal-sized sections labeled 1 to 7. What is the probability that Jewel will spin a 7?

• about 7%

• about 14%

• about 21%

• about 28%

Tags

CCSS.7.SP.C.7A

Jamey has 4 quarters, some dimes, and some pennies. If the ratio of quarters to dimes is 8 : 6 and the ratio of pennies to dimes is 7 : 3, then how many pennies does Jamey have?

• 6

• 8

• 3

• 7

Toni orders school lunch on Mondays, Wednesdays, and Fridays. On what percentage of weekdays does Toni NOT order school lunch?

• 20%

• 30%

• 40%

• 60%

The random numbers below represent 10 trials of a simulation.

2632, 1365, 9367, 2056, 0026, 6564, 1434, 8045, 4781, 8681

The numbers 0–7 represent students who watched television last night, and the numbers 8 and 9 represent students who did not. Based on the simulated data, what is the probability that exactly 2 out of a group of 4 randomly selected students watched television last night?

• 1/10

• 4/10

• 5/10

• 9/10

Tags

CCSS.7.SP.C.8C

The yearbook club is handing out T-shirts to its members. There are 5 blue, 7 green, 9 red, and 4 yellow T-shirts in all. If Jacob is handed a T-shirt, what is the probability that the color is red?

• 9/25

• 9/16

• 3/5

• 16/25

Tags

CCSS.7.SP.C.7B