A telecommunications company commissioned a study to investigate the amount of time that people spend on phone calls. The study that found that the length of time that people spend on a phone call is approximately normally distributed with a mean of 484 seconds and a standard deviation of 93.7 seconds. Calculate the standardized value (z) for a time of 620 seconds. Give your answer to 2 decimal places.

Question

Mathematics

Tiara Preston

26 March, 23:11

A telecommunications company commissioned a study to investigate the amount of time that people spend on phone calls. The study that found that the length of time that people spend on a phone call is approximately normally distributed with a mean of 484 seconds and a standard deviation of 93.7 seconds. Calculate the standardized value (z) for a time of 620 seconds. Give your answer to 2 decimal places.

+4

Answers (1)

Know the Answer?

Keira Stevenson · Answer 1

standardized z value for 620 seconds = 1.45

Step-by-step explanation:

The standardized z value can be calculated as

standardized z value = (given time-mean time) / S. D of time i. e. z = (x-mean) / S. D.

standardized z value = (620-484) / 93.7

standardized z value=136/93.7

standardized z value=1.45

The calculated standardized z value for a time of 620 seconds is 1.45.