SOLUTION: What is the smallest positive integer n for which 324 is a factor of 6^n? (A) 2 (B) 3 (C) 4 (D) 5 (E) 6

Algebra.Com
Question 165477: What is the smallest positive integer n for which 324 is a factor of 6^n?
(A) 2 (B) 3 (C) 4 (D) 5 (E) 6

Found 2 solutions by MRperkins, Edwin McCravy:
Answer by MRperkins(300)   (Show Source): You can put this solution on YOUR website!
Factor 324 completely:



Continue doing this until you have all of the factors of 324. It is ok to have additional factors but it is not ok to be missing any factor.
notice that we are still missing a 3 in this one
here we finally have two (2)'s and the four (3)'s that are in 324 and we also have two (2)'s left over.
6^4 =324(the factor of 6^4) times the two (2)'s that are left over
so 6^4=1296
Edwin is correct that (c)4 is the right answer.

Answer by Edwin McCravy(20054)   (Show Source): You can put this solution on YOUR website!
Edwin's solution:
What is the smallest positive integer n for which 324 is a factor of 6^n?
(A) 2 (B) 3 (C) 4 (D) 5 (E) 6

Break 324 down into primes

324 = 2*2*3*3*3*3

Since 6 = 2*3, each factor of 6 contributes one factor of 2 
and one factor of 3.

Since 324 has four factors of 3, we need four factor of 6 to
contribute them all.

So the answer is 4, choice (C)

Edwin

RELATED QUESTIONS

Suppose a positive integer n is divisible by 21 and by 9. What is the smallest possible... (answered by Edwin McCravy)
If n is an integer, which of the following CANNOT be a factor of 3n + 4 ? (A)... (answered by MRperkins)
What is the smallest integer u, for which 5u>625 A) 3 B) 4 C) 5 D) 6 E) None of... (answered by Alan3354)
If a non-zero integer n is chosen such that (2-16/n) is an integer less than 6 Which of (answered by stanbon,Edwin McCravy,vleith)
if n+4 represent an odd integer the next larger odd integer is represented by a) n+2... (answered by Alan3354)
If n is a positive integer and {{{(n+1)/2^n = 1/2}}}, then n= a.1 b.2 c.3 d.4... (answered by Edwin McCravy)
If n is a positive integer and n+1/2^n=1/2 then n= a. 1 b. 2 c.3 d. 4... (answered by Edwin McCravy)
If n is a positive integer, which of the following cannot be the units digit of 7^n?... (answered by Alan3354)
If n is a positive integer, which of the following cannot be the units digit of 7^n ?... (answered by JBarnum)