7th Grade Probability

Theoretical

100

The classic wood carousel at Carousel Park in Hampton, VA has 32 jumping horses and 16 standing horses. What is the probability of randomly selecting a jumping horse (in simplest form)?

2/3

200

The theoretical probability of rolling a 4 on a fair die is 1/6. In an experiment, a die is rolled 60 times and a 4 appears 12 times. What is the experimental probability of rolling a 4?

12/60 or 0.20, or 20%

300

What is the probability of rolling two odd numbers in a row with a standard number cube?

1/4, or 0.25, or 25%

400

A card is drawn from a standard deck of 52 cards. What is the theoretical probability of drawing a king?

4/52 or 1/13

500

Calculate the probability of rolling a sum of 7 when two dice are rolled.

6/36

Experimental

100

A spinner is spun 20 times.  If you land on red 6 times, what is the experimental probability of getting red (in simplest form)?

3/10

200

Pedro recorded the types of birds that visit his bird feeder. Based on the results below, what is the probability the next bird will be a chickadee? Woodpecker = 3 Chickadee = 5 Cardinal = 1 Sparrow = 13 Blue Jay = 3

1/5, or 0.20, or 20%

300

In an experiment, a coin is tossed 50 times and lands on heads 28 times. What is the experimental probability of getting heads?

28/50 or 0.56, or 56%

400

A company finds that 4 out of 150 of its magnifying glasses are defective. Based on this information, predict how many defective magnifying glasses you would expect to find in a batch of 2,000.

about 53 magnifying glasses

500

A six-sided die is thrown 50 times and a three is rolled 10 times.  Based on this experiment, how many times would you expect to get a three if the die is rolled 120 times?

24 times

Counting Principle

100

What is the sample space for rolling a single fair die?

{1,2,3,4,5,6}

200

What is the number of possible outcomes for spinning one spinner with 8 equal sections and another spinner with 6 equal sections?

48 possible outcomes

300

Using the Fundamental Counting Principle, how many possible outcomes are there when rolling two dice?

36

400

Ms. French is packing for a trip. She packs a white blouse, a pink blouse, a blue blouse, and a green blouse. She also packs a black suit, a navy blue suit, and a gray suit. What is the probability that the first outfit she wears is the gray suit with a pink blouse?

1 out of 12

500

A password consists of 2 letters followed by 3 digits. How many different passwords are possible?

26×26×10×10×10=676,000

Measures of Variation

100

Find the range of: 10, 6, 11, 14, 25, 13

19

200

The following are examination scores of 10 students: 70, 75, 80, 85, 90, 65, 70, 80, 85, 90. Which measure of variability would best describe how much the scores differ from the average?

Mean Deviation or Standard Deviation

300

If the variance of a given set of data is 4, What is the standard deviation?

2

400

The mean deviation of a data set measures what?

The average distance of each data point from the mean

500

What is the other term for measures of variability?

Measures of dispersion

Measures of Central Tendency

100

Find the mean for the following set: 45, 45, 47, 49, 50, 52

 288/ 6 = 48

200

Give a definition for mode.

The value that occurs most often.

300

Find the median: 8, 22, 15, 11, 10

11

400

Find the mean of: 10, 15, 22, 30, 45

24.4

500

Find the median and mode: 25, 16, 18, 16, 24, 30

median 21 and mode 16