If n is the product of 3 consecutive integers, which of the following

Question

If n is the product of 3 consecutive integers, which of the following must be true?

I. a multiple of 2
II. a multiple of 3
III. a multiple of 4

A. I only
B. II only
C. III only
D. I and II
E. II and III

BrentGMATPrepNow · Accepted Answer

There's a nice rule says:   The product of k consecutive integers is divisible by k, k-1, k-2,...,2, and 1  
So, for example, the product of  any  5 consecutive integers will be divisible by 5, 4, 3, 2 and 1
NOTE: the product may be divisible by other numbers as well, but these divisors are guaranteed.

In this question, n is the product of 3 consecutive integers. 
So, according to the   rule  , n must be divisible by 3, 2 and 1
So, we already know that statements I and II must be true.

Do we need to check statement III? No. 
Notice that NONE of the answer choices include all 3 statements. Since we've already concluded that statements I and II are true, the correct answer is D.

HOWEVER, if you want to check statement III, notice that the product of 1, 2 and 3 (3 consecutive integers) is 6, and 6 is not divisible by 4

Abhishek009 · Answer

There is a property which states -

So, n will be a multiple of 2 and 3
  
Answer will be (D)

MathRevolution · Answer

==> The product of 3 consecutive integers always become the multiple of 6, because the product always contains 3 and 2. Thus, in this question, it always becomes the multiple of 6 that contain 3 and 2, I and II are the answer. Therefore, the answer is D. III does not work because it becomes 1*2*3*=6, hence it cannot be the multiple of 4.

Answer: D

Answer: D

broall · Answer

Among 3 consecutive integers, there is always at least one even integers, so n is divisible by 2. (I) is true

Among 3 consecutive integers, there is always only one integers divisible by 3, so n is divisible by 3. (II) is true.

3 consecutive integers could be even-odd-even or odd-even-odd.
If they are even-odd-even, n is divisible by 4.
If they are odd-even-odd, n is not divisible by 4. For example,  n=1 	imes 2 	imes 3 =6  is not divisible by 4.
Hence, (III) is not true.

Thus, the answer is D.

stonecold · Answer

Product of n consecutive integers is always divisible by n! 
So n will be of the form 6k for some integer k.
Clearly it will always be divisible by 2 and 3 but may/may not be divisible by 4.

Hence D.

JeffTargetTestPrep · Answer

Since n is the product of 3 consecutive integers, n is divisible by 3! = 6. Since 2 and 3 are factors of 6, Roman numerals I and II must be true.

Answer: D

rai0512 · Answer

can the integers be -1,0 and 1? in that case nothing holds true. I think it should have mentioned n not equal to 0.

MathRevolution · Answer

==> If n is the product of 3 consecutive integers, it is always even and has 3, so it is always a multiple of 6. Thus, I and II is correct and for III, since n=1*2*3=6 is not a multiple of 4, hence it is incorrect.

The answer is D.
Answer: D

The answer is D.
Answer: D

Bunuel · Answer

No, that's not right. You should know that  0 is divisible by every integer except 0 itself .

Shiv2016 · Answer

In three consecutive nos. one number (at least) will be 2 or a multiple of 2 thus making the product even. Thus divisible by 2.

The product of three consecutive nos. is always divisible by 3. 
For example, 4*5*6 (6 is a multiple of 3)
7*8*9 (9 is a multiple of 3)

matthewsmith_89 · Answer

Something you all need to know, an integer multiplied by the second and third consecutive will always be divisible by 2 and 3.
For an example
1 x 2 x 3.
There is no need to do any working out here. We all know that it is divisible by 2 and 3.
Therefore, the answer is D

bumpbot · Answer

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If n is the product of 3 consecutive integers, which of the following

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If n is the product of 3 consecutive integers, which of the following

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