7th Grade Math

Lesson 3A Predictions 461

= Step-by-Step Solutions begin on page R1.

Extra Practice begins on page EP2.

Examples 1–3 3. A number cube is rolled 20 times and lands on 1 two times and on

5 four times.

a. Find the experimental probability of landing on 5. Compare the

experimental probability to the theoretical probability.

b. Find the experimental probability of not landing on 1. Compare the

experimental probability to the theoretical probability.

Examples 4 and 5 4. ZOO Use the graph of a survey of 70 zoo visitors who were

asked to name their favorite animal exhibit.

a. What is the probability that

the elephant exhibit is

someone’s favorite?

b. What is the probability

that the bear exhibit

is someone’s favorite?

c. Suppose 540 people visit

the zoo. Predict how

many people will choose

the monkey exhibit as

their favorite.

d. Suppose 720 people visit the zoo. Predict how many people will

choose the penguin exhibit as their favorite.

B^55 MULTIPLE REPRESENTATIONS A spinner with three Section Frequency

A24

B50

C26

equal-sized sections marked A, B, and C is spun

100 times.

a. NUMBERS What is the theoretical probability of

landing on A?

b. NUMBERS The results of the experiment are shown in the table.

What is the experimental probability of landing on A? on C?

c. MODELS Make a drawing of what the spinner might look like based

on its experimental probabilities. Explain.

6. GIFTS Use the graph at the

28% 40%

8%

8%

7%

6%

3%

card

flowers/plants

dinner/brunch

apparel

jewelry

home décor

Most Popular Mother’s Day Gifts

gardening

items

right.

a. What is the probability

that a mother received a

gift of flowers or plants?

Write the probability as a

fraction in simplest form.

b. Out of 400 mothers that

receive gifts, predict how

many will receive flowers

or plants.

Exhibit Tally Frequency

Bears 6

Elephants 17

Monkeys 21

Penguins 13

Snakes 13

What is your Favorite

Animal Exhibit?

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