昨天做了princeton的模考，但2道数学题的答案把我搞晕了，请高手帮助答疑
1.What is the largest integer X such that 8 less than 5 times X is less than 43?
the answer is 10
请高手列出解体思路
2. For all integers P, f is the number of distinct factors of P that divisible by 3 or 2, if P=36,f=?
answer is 8
factor是否包含1和本身？
多谢作者: smart 时间: 2004-3-16 16:28
对不起，我也没能很好的理解题意，不能给出解题思路。
请高手指教。作者: dancingforum 时间: 2004-3-17 00:42
1st question:
5 * X - 8 < 43 ===> X < 10.2
the largest integer satisfying the above is of course 10 作者: dancingforum 时间: 2004-3-17 01:16
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2. For all integers P, f is the number of distinct factors of P that divisible by 3 or 2, if P=36,f=?
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my thought:
step 1: Understand what the question says about F
F is the number of P's factors such that:
a) each factor has to be DISTINCT ( unique)
b) each factor has to be divisible by EITHER 3 OR 2 OR 2*3
step 2: solve the problem which is actually a combination question
