[求助]求助GWD1-15

poorleafs

If p is the product of the integers from 1 to 30, inclusive, what is the greatest integer k for which 3^k is a factor of p?

a) 10

b) 12

c) 14

d) 16

e) 18

<C>

不懂题目 所以不知该如何计算 感谢帮忙...

poorleafs

所以要一个个去除吗？