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Chapter 7: Q. 21 (page 464)

A large company is interested in improving the efficiency of its customer service and decides to examine the length of the business phone calls made to clients by its sales staff. A cumulative relative frequency graph is shown below from data collected over the past year. According to the graph, the shortest 80%of calls will take how long to complete?

(a) Less than10 minutes.
(b) At least10 minutes.
(c) Exactly10 minutes.
(d) At least5.5 minutes.
(e) Less than 5.5minutes.

Short Answer

Expert verified

The shortest of 80%of cell takes less than10minutes. So, the option (a) is correct.

Step by step solution

01

Given information

A cumulative relative frequency graph is shown below from data collected over the past year.

02

Explanation

In the graph, minutes are measured on horizontal axis and percent on vertical axis. A line is drawn that touches the blue curve joining to vertical axis and horizontal axis is shown below:

From the graph, concluded that the shortest 80%of the calls are less than10 minutes.
Hence, the correct option is (a).

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