Question

here are the shopping times (in minutes) for each of eighteen shoppers at a local grocery store.

(a) complete the grouped frequency distribution for the data. (note that the class width is 6.)
(b) construct a histogram for the data.

Explanation:

Step1: Count data in 15 - 20

Data: 17, 15, 18. Frequency = 3.

Step2: Count data in 21 - 26

Data: 23, 25, 21, 21, 24. Frequency = 5.

Step3: Count data in 27 - 32

Data: 34, 32, 27, 31, 30, 28, 26. Frequency = 7.

Step4: Count data in 33 - 38

Data: 38, 35, 37. Frequency = 3.

Answer:

15 to 20: 3; 21 to 26: 5; 27 to 32: 7; 33 to 38: 3.