Question

(a) complete the grouped frequency distribution for the data. (note that the class width is 6.)
shopping times (in minutes) frequency
14.5 - 20.5
20.5 - 26.5
26.5 - 32.5
32.5 - 38.5
(b) construct a histogram for the data.
frequency

Explanation:

Step1: Count data in 14.5 - 20.5

The numbers in this range are 17, 18, 15. So the frequency is 3.

Step2: Count data in 20.5 - 26.5

The numbers are 26, 21, 21, 25, 23. The frequency is 5.

Step3: Count data in 26.5 - 32.5

The numbers are 30, 32, 27, 31, 28. The frequency is 5.

Step4: Count data in 32.5 - 38.5

The numbers are 34, 37, 35, 38. The frequency is 4.

Answer:

Shopping times (in minutes)	Frequency
20.5 - 26.5	5
26.5 - 32.5	5
32.5 - 38.5	4

For part (b), to construct a histogram:

• On the x - axis, label the intervals 14.5 - 20.5, 20.5 - 26.5, 26.5 - 32.5, 32.5 - 38.5.
• On the y - axis, label the frequency from 1 to 7.
• Draw bars with heights corresponding to the frequencies calculated above for each interval.