Question

GRE数学！~~求解~

In a distribution of 8,500 different measurements of the variable x, 26.5 is the 56th
percentile and 37.1 is the 78th percentile. Which of the following is closest to the number of measurements of x that are in the distribution such that 26.5 ≤ x ≤37.1 ?
A. 1,850
B. 2,200
C. 3,500
D. 4,750
E. 6,650

Answer 1

（78-56）/100*8500
比2200小。所以是A

追问

能具体解释下为什么要这么算吗？谢谢~

追答

一堆长度从小到大排26.5排在56%，37.5排在78%，x就是这中间22%的任何一个，总量8500，所以x有8500*22%个