The scores of students on a standardized test form a normal distribution with a mean of 300 and a standard deviation of 40. What are the lower and upper quartile scores for this test?
A) 280 and 320
B) 273 and 327
C) 260 and 340
D) 150 and 450

Question

Quizplus · Accepted Answer

The lower quartile will be one standard deviation below the mean which is 300 - 40 = 260. The upper quartile will be one standard deviation above the mean which is 300 + 40 = 340. Therefore, the answer is B, with lower quartile 273 and upper quartile 327, which covers the middle 50% of the distribution.

The Scores of Students on a Standardized Test Form a Normal