Data & Statistics - Unit Test A

1. A grocery store polls every twentieth customer to determine if they are satisfied with the cleanliness of the store. Forty customers are surveyed, and 26 are satisfied. What conclusion can be drawn for the 800 daily customers?

• A. 65% of the customers are unsatisfied with the cleanliness of the store.
• B. Of the 800 customers, 520 would be satisfied with the cleanliness of the store.
• C. 40% of the customers are satisfied with the cleanliness of the store.
• D. 25% of the customers are not satisfied with the cleanliness of the store.

2. At the zoo, the length of each iguana is measured. Which statement is best supported by the information below?

• A. Over half of the iguanas measure 14 centimeters or more in length.
• B. 25% of the iguanas measure 12 centimeters in length.
• C. The number of iguanas that measure 15 centimeters or more is equal to the number that measure 11 centimeters or less.

3. If there are 220 members of the 7th grade class, then how many students can be expected to prefer the zoo?

• A. 39
• B. 48
• C. 120
• D. 66

4. If there are 180 members of the 8th grade class, then what percent preferred either the museum or the sports complex?

• A. 65%
• B. 47.5%
• C. 17.5%
• D. 26%

5. Which of the conclusions best supports the dot plots?

• A. Both Jamal’s and Kendall’s racecars had an equal spread in their data.
• B. On average Kendall’s race car traveled further.
• C. The median Jamal’s race car traveled was 6.5 ft.
• D. Both Jamal and Kendall had the same mode of data.

6. Which of the following represents the mean absolute deviation of Jamal’s data?

• A. 6.4
• B. 1.12
• C. 2.8
• D. 0.9

7. Which of the following statements does NOT represent the data?

• A. The scores in Mrs. Ruiz’s class have less variability than the scores in Mrs. Moore’s class.
• B. The median of Mrs. Moore’s class is equal to the first quartile of Mrs. Ruiz’s class.
• C. The interquartile range of both classes is equal.
• D. The scores in Mrs. Moore’s class have a greater spread than the scores in Mrs. Ruiz’s class.

8. Which of the following represents the difference in centers of Mrs. Moore’s class and Mrs. Ruiz’s class?

• A. 7
• B. 11
• C. 4
• D. 3

9. Data is collected from a random sample of 40 people at the public library. If the public library has 300 patrons, then which of the following conclusions can be drawn?

• A. Exactly 42% of the library patrons chose a mystery.
• B. Non-fiction and science fiction represent over half of the selections.
• C. Over 25% of the library patrons chose a science fiction book.
• D. 136 total patrons can be expected to choose a non-fiction book.

10a. What is the median of the first half of the data? (first quartile)