What is the product of all positive factors of 18?

Question

A. 39 
B. 324 
C. 1521 
D. 3042 
E. 5832

livio04 · Answer

Positive factors of 18 are 1,2,3,6,9, and 18. The factors set up 3 pairs of 18 (18*1, 2*9, 3*6), hence its product is 18^3, which is 5832. I would go for E, then.

saraswatpraveen07 · Answer

Prime Factorization of 18 = 2^   1    * 3^   2   
Therefore number of factors of 18 = (   1   +1)*(   2   +1) = 6 = say  A

{factors of 18 are (1,18) , (2,9) , (3,6) i.e 6 in number}

Now product of all factors of 18 = 18^(  A  /2) = 18^(6/2) = 18^3 = 5832 (Answer is E)

stonecold · Answer

Here is the my way to solve this Question
The product should be divisible by 2 => Reject A,B,C
now product is >3240 as P=1*2*3**6*9*18 = 324 *18 => do not compute further
hence E

mvictor · Answer

all positive factor of 18 are:
18, 9, 6, 3, 2, and 1.
3*2 = 6.
6*6 = 36
18*9 = smth smth 2

36* smth smth 2 = last digit is 2.
A, B, C are out.

since we have 18 (has a factor of 2), then 6 (has another factor of two), then another 2. the number itself must contain at least 3 factors of two.
3042 /2 = 1521 - ouch, no more factors of two.

E is the answer.

Abhishek009 · Answer

No issues with the approach, however the calculations ( in the highlighted part ) can be simplified - 18 x 9 ~ 18 x 10 = 180 180 x 6 = 1080 1080 x 3 = 3024 3024 x 2 = Will be Greater than option (D) Hence answer will definitely be (E) :-D

stonecold · Answer

Just Another Approach could be => The unit digit method
The unit digit of 1*2*3*6*9*18 => 2
so we know that D or E is the Answer.
Now D can't be the answer since 3042=2*9*13*13
and 13 is clearly not a prime factor of 18
hence E must be true

ScottTargetTestPrep · Answer

The positive factors of 18 are:

1, 2, 3, 6, 9, 18

The product of the first 4 numbers in the list is 36 and the product of the last two is 162. Therefore, the product of all the numbers in the list is:

36 x 162 = 5,832

Answer: E

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What is the product of all positive factors of 18?

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What is the product of all positive factors of 18?

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