Question

The graph shows the distribution of the lengths (in seconds) of videos on a popular video-streaming site. The distribution is approximately Normal, with a mean of 264 seconds and a standard deviation of 75 seconds.

A graph titled Streaming Videos has length (seconds) on the x-axis, going from negative 36 to 564. The highest point of the curve is at 264.

What percentage of videos on the streaming site are between 39 and 189 seconds?

0.15%
15.85%
16%
34%

Answer 1

The percentage of videos on the streaming site are between 39 and 189 seconds is 15.85%

What percentage of videos on the streaming site are between 39 and 189 seconds?

From the question, we have the following parameters that can be used in our computation:

Mean = 264

Standard deviation = 75

Also, we have

Scores = 39 and 189 seconds

The z-score at x = 39 and 189 is

z = (x - Mean)/SD

So, we have

z = (39 - 264)/75 and z = (189 - 264)/75

z = -3 and z = -1

The percentage is then calculated as

P = (-3 < z < -1)

Using the z-table of probabilities, we have

P = 0.1585

This gives

P = 15.85%

Hence, the percentage is 15.85%