If \(n\) divided by 7 has a remainder of 2, what is the

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by [email protected] » Sun Dec 01, 2019 1:56 pm
Hi VJesus12,

We're told that when N is divided by 7, the remainder is 2. We're asked for the remainder when 3N is divided by 7. This question can be solved rather easily by TESTing VALUES.

N can actually be lots of different values, so I'll list out the first several: N/7 = __ r 2...... N = 2, 9, 16, 23, 30, etc.

IF.... N=9...
3(9)/7 = 27/7 = 3 r 6

So the remainder is 6.

Final Answer: E

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by Scott@TargetTestPrep » Thu Dec 05, 2019 7:05 pm
VJesus12 wrote:If \(n\) divided by 7 has a remainder of 2, what is the remainder when 3 times n is divided by 7?

A. 1
B. 2
C. 3
D. 5
E. 6

[spoiler]OA=E[/spoiler]

Source: Manhattan GMAT
We can let n = 2. Thus:

(3 x 2)/7 = 6/7 = 0 remainder 6.

Answer: E

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by Brent@GMATPrepNow » Fri Dec 06, 2019 6:54 am
VJesus12 wrote:If \(n\) divided by 7 has a remainder of 2, what is the remainder when 3 times n is divided by 7?

A. 1
B. 2
C. 3
D. 5
E. 6
----ASIDE-------------------------
When it comes to remainders, we have a nice rule that says:
If N divided by D leaves remainder R, then the possible values of N are R, R+D, R+2D, R+3D,. . . etc.
For example, if k divided by 5 leaves a remainder of 1, then the possible values of k are: 1, 1+5, 1+(2)(5), 1+(3)(5), 1+(4)(5), . . . etc.
-----------------------------

In this case we are told that n divided by 7 leaves a remainder of 2
So the possible values of n are: 2, 9, 16, 23, etc....

So let's say n equals 2
The question becomes "What is the remainder when 3 times 2 is divided by 7?"
In other words, "What is the remainder when 6 is divided by 7?"
7 divides into 6 zero times, leaving a remainder of 6

Answer: E


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