If n = pqr, where p, q, and r are three different positive prime numbers, how many different positive divisors does n have, incl

admin2009-05-19  34

问题 If n = pqr, where p, q, and r are three different positive prime numbers, how many different positive divisors does n have, including 1 and n?

选项 A、3
B、5
C、6
D、7
E、8

答案E

解析 若n=pqr,其中p,q,r是3个不同的正质数(positive prime numbers),n有多少个不同的因子,包括1和n?
解:本题的正确答案为(E)。由因子数求解公式可得n=p×q×r,当p,q,r为质数时n的因子数为(1+1)(1+1)(1+1)=8个。
转载请注明原文地址:https://jikaoti.com/ti/GKdYFFFM
本试题收录于: GRE QUANTITATIVE题库GRE分类
0

最新回复(0)