求助一道prep2013 pack1中的一道数学题

anslynn

For every positive even integer n, the function h(n) is defined to be the product of all the even integer from 2 to n, inclusive, if p is the smallest prime factor of h(100)+1, then p is ?

A. between 2 and 10
B. between 10 and 20
C. Between 20 and 30
D. between 30 and 40
E. greater than 40

正确答案是E

请大牛帮忙求解，非常感谢~~~

anslynn

peterxk 发表于 2013-9-15 14:14
h(100)=2x4x6x...100=2^50 x 50!
就是说1到50都是他的因子
而两个连续非零自然数互质

膜拜~~再请教一题

the instructions for computing income tax in Country R were to add 2% of one's annual income to the average (arithmetric mean) of 100 units of country R's currency and 1% of one's annual income. Which of following represents the simplified formula for the computing the income intax, in Country R's currency, for a person in that country whose annual income is I?

正确答案是 50+I/40

请问如何求解，关键不理解“the average (arithmetric mean) of 100 units of country R's currency ”是什么意思

anslynn

bergkamp91 发表于 2013-9-15 14:55
是The average of后面两个东西，一个是100货币单位（这是个缺心眼的表达方法，对解题没有意义的，你就理 ...

哦，明白了，非常感谢~！

anslynn

elsachialee 发表于 2013-9-16 13:26
就是income是I
所以公式是2％＊I＋［（100＋1％＊I）／2］。关键是要理解那个100个units currency的意思 ...

非常感谢！