Grade: Grade 7 Subject: Mathematics Unit: Probability Lesson: 6 of 6 SAT: ProblemSolving+DataAnalysis ACT: Math

Unit Checkpoint

Demonstrate mastery of probability concepts.

Checkpoint Questions

Question 1: What is the probability of rolling a 5 on a fair die?

Answer

P(5) = 1/6

Question 2: A bag has 4 red, 3 blue, 3 green marbles. What is P(blue)?

Answer

P(blue) = 3/10

Question 3: In 50 tosses, a coin landed heads 32 times. What is the experimental probability of heads?

Answer

P(heads) = 32/50 = 16/25 = 0.64 or 64%

Question 4: Flip a coin and roll a die. What is P(tails and even)?

Answer

P(tails) = 1/2, P(even) = 3/6 = 1/2. P(tails and even) = 1/2 x 1/2 = 1/4.

Question 5: How many outcomes are in the sample space for spinning a 4-section spinner twice?

Answer

4 x 4 = 16 outcomes

Question 6: What is P(rolling an even number OR a number less than 3)?

Answer

Even: {2,4,6}. Less than 3: {1,2}. Union: {1,2,4,6}. P = 4/6 = 2/3.

Question 7: Draw 2 cards without replacement from a deck. P(both aces)?

Answer

P(first ace) = 4/52. P(second ace) = 3/51. P(both) = 12/2652 = 1/221.

Question 8: A spinner landed on red 45 times in 150 spins. Estimate P(red).

Answer

P(red) = 45/150 = 3/10 = 0.30 or 30%

Question 9: Roll two dice. What is P(sum = 12)?

Answer

Only (6,6) gives sum 12. P = 1/36.

Question 10: Explain how to use a die to simulate a 1/3 probability.

Answer

Roll the die. If 1 or 2, success (2 out of 6 = 1/3). If 3-6, failure.