Chapter 7: Q.AP2.21 - Cumulative AP Practise Test (page 438)

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. Here is a cumulative relative frequency graph from data collected over the past year. According to the graph, the shortest 80%of calls will take how long to complete?

a. Less than 10 minutes

b. At least 10 minutes

c. Exactly 10 minutes

d. At least 5.5minutes

e. Less than 5.5minutes

Short Answer

Expert verified

a. Less than 10 minutes

Step by step solution

01

Given Information

02

Explanation for correct option

Finding 80%on the Y-axis, sketch a line to the right side until it touches the blue graph. Therefore it is cumulative; everything to the left side would be less than 10 minutes. The value will be 10 minutes therefore the shortest 80%of the call would be less than 10 minutes.

Hence, the correct option is (a)

03

Explanation for incorrect option

b. At least 10 minutes is not the answer.

c. Exactly 10 minutes is not the answer.

d. At least 5.5 minutes is not the answer.

e. Less than 5.5 minutes is not the answer.

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