The average math SAT score is 518 with a standard deviation

The average math SAT score is

518 with a standard deviation of 117

A particular high school claims that its students have unusually high math SAT scores. A random sample of

60 students from this school was selected, and the mean math SAT score was

540 Is the high school justified in its claim? AND WHAT IS THE Z SCORE PLEASE

unusual

not unusual

since it

lies

does not lie

within the range of a usual event, namely within

1 standard deviation

2 standard deviations

3 standard deviations

of the mean of the sample means.

(Round to two decimal places as needed.)

Solution

If we define \"usual\" as within 2 standard deviations from the mean,

z = (X - u) * sqrt(n) / sigma = (540 - 518)*sqrt(60) / 117 = 1.456506558 [ANSWER, Z SCORE]

****************

Thus, it is

1. NOT UNUSUAL

since it

2. LIES

within the range of a usual event, namely within

3. 2 STANDARD DEVIATIONS

of the mean of the sample means.