求助一道关于奇偶性的题

iforone

How many 4-digit positive integers are there in which all 4 digits are even?

 

A.    625

B.     600

C.     500

D.    400

E.     256

请问该怎么算呢?谢谢!

germaineilya

4 digit positive integers

so for the first digit , it can be 2,4,6,8 (cant be zero)

for the rest of the digits it can be 0 2 4 6 8

so the ways of combinations : 4*5*5*5=500

so answer is c I think

hedgeshrew

我也觉得是500，有正确答案的密一下