Statistics and Probability 8

A survey showed that 28% of adults do not own a cell phone. Out of 1,550 adults, 434 adults would say that they do not own a cell phone.

• True

• False

Answer explanation

28% of 1,550 adults is 434 (0.28 * 1550 = 434). Since the survey shows that 434 adults do not own a cell phone, the statement is true.

What is the probability that a person chooses basketball as their favorite sport?

• 20

• 20/50

• 2/5

• 20%

Answer explanation

The probability of choosing basketball is represented as a fraction of favorable outcomes over total outcomes. If 20 out of 50 people choose basketball, this simplifies to 2/5, which is the correct answer.

The probability of spinning blue on Victor's spinner is 1. Which word best describes the chance of spinning blue on Victor's spinner?

• impossible

• unlikely

• likely

• certain

Answer explanation

The probability of spinning blue is 1, meaning it will definitely happen. Therefore, the best word to describe this chance is 'certain', indicating that spinning blue is guaranteed.

What is the probability of spinning a 5?

• 5/8

• 1

• 5

• 1/8

Answer explanation

A standard spinner has 8 equal sections. The probability of landing on any specific number, like 5, is 1 out of 8 sections. Therefore, the probability of spinning a 5 is 1/8.

P(even number)

• 1

• 1/2

• 4

• 4/8

Answer explanation

The probability of rolling an even number on a standard die (1, 2, 3, 4, 5, 6) is 3 out of 6 (2, 4, 6), which simplifies to 1/2. Thus, the correct answer is 1/2.

P(even number)

• 1

• 1/2

• 4

• 4/8

Answer explanation

The probability of rolling an even number on a standard die (1, 2, 3, 4, 5, 6) is 3 out of 6 (2, 4, 6), which simplifies to 1/2. Thus, the correct answer is 1/2.

The weather reporter says that there is a 14% chance of rain tomorrow. What is the probability that it will not rain?

• 14%

• 50%

• 64%

• 86%

Answer explanation

The probability of it not raining is the complement of the chance of rain. If there is a 14% chance of rain, then the chance of no rain is 100% - 14% = 86%. Therefore, the correct answer is 86%.

Bob flips a coin. He also spins the spinner. What is the probability that Bob flips a tails and spins a 2?

• 1/2

• 1/8

• 1/16

• 1/3

Answer explanation

The probability of flipping tails is 1/2 and spinning a 2 (assuming 4 equal sections) is 1/4. Multiply these probabilities: (1/2) * (1/4) = 1/8. However, if the spinner has 4 sections, the total outcomes are 2 (tails or heads) * 4 (spinner) = 8. Thus, 1/16 is correct.

What is the probability that you choose blue?

5 green

6 yellow

8 blue

7 brown

• 8/26

• 4/13

• 8/25

• 1/3

Answer explanation

To find the probability of choosing blue, divide the number of blue marbles (8) by the total number of marbles (5 green + 6 yellow + 8 blue + 7 brown = 26). Thus, the probability is 8/26, which simplifies to 4/13.

What is the probability of spinning an even number?

• 16 2/3%

• 33 1/3%

• 50%

• 75%

Answer explanation

In a standard spinner with numbers 1 to 6, the even numbers are 2, 4, and 6. There are 3 even numbers out of 6 total numbers, giving a probability of 3/6, which simplifies to 50%.