Given that on one section of the SAT the mean is 500 and the standard deviation is 100,what is the approximate probability of a student scoring 400 or lower on the test?
A).84
B).50
C).16
D).34

Question

Given that on one section of the SAT the mean is 500 and the standard deviation is 100,what is the approximate probability of a student scoring 400 or lower on the test? 
A).84
B).50
C).16
D).34

Quizplus · Accepted Answer

To solve this problem, we need to use the standard normal distribution. First, we need to convert the raw score of 400 to a z-score:

z = (400 - 500) / 100 = -1

We then look up the probability of getting a z-score of -1 or lower in a standard normal distribution table, which is approximately 0.16 or 16%.

Therefore, the answer is (C) 16.

Given That on One Section of the SAT the Mean