A videotape store has an average weekly gross of $1,158 with a standard deviation of $120.Let x be the store's gross during a randomly selected week.If this is a normally distributed random variable,then the number of standard deviations from $1,158 to $1,360 is:
A) 0.4535.
B) 0.0465.
C) 20.98.
D) 1.683.
E) none of these.

Question

Quizplus · Accepted Answer

To find the number of standard deviations from $1,158 to $1,360, we need to first find the z-score, which tells us how many standard deviations a given value is from the mean.

z-score = (x - mean) / standard deviation

Plugging in the values given:

z-score = (1360 - 1158) / 120 = 1.683

So the number of standard deviations from $1,158 to $1,360 is 1.683.

Therefore, the answer is D.

A Videotape Store Has an Average Weekly Gross of $1,158