Please help!
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From the question stem we have to find if n is a multiple of 15 i.e. 5 and 3
If we know that n is a multiple of 5 and 3 both n will also be a multiple of 15.
Statement I
n is a multiple of 20
20= 2*5*2
This means that n will be a multiple of 5 for sure, but we dont know anything about 3. Therefore insufficient.
Statement II
n+6 is a multiple of 3 this means that n is a multiple of 3, but we dont know anything about 5. Therefore insufficient.
Statement I & II
n is a multiple of 5, n is multiple of 3, therefore n has to be a multiple of 15.
Here is rule that you can learn. It is regarding how I found that n will be a multiple of 3 in II statement n+6 is a multiple of 3
If a and b are divisible by n then a-b & a+b both will be divisible by n.
Let me know if you have any doubts.
If we know that n is a multiple of 5 and 3 both n will also be a multiple of 15.
Statement I
n is a multiple of 20
20= 2*5*2
This means that n will be a multiple of 5 for sure, but we dont know anything about 3. Therefore insufficient.
Statement II
n+6 is a multiple of 3 this means that n is a multiple of 3, but we dont know anything about 5. Therefore insufficient.
Statement I & II
n is a multiple of 5, n is multiple of 3, therefore n has to be a multiple of 15.
Here is rule that you can learn. It is regarding how I found that n will be a multiple of 3 in II statement n+6 is a multiple of 3
If a and b are divisible by n then a-b & a+b both will be divisible by n.
Let me know if you have any doubts.
@parallel chase
Thank you.
can you please elaborate this,,,,Even i choose E.n is a multiple of 5, n is multiple of 3, therefore n has to be a multiple of 15.
Here is rule that you can learn. It is regarding how I found that n will be a multiple of 3 in II statement n+6 is a multiple of 3
If a and b are divisible by n then a-b & a+b both will be divisible by n.
Thank you.
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- Legendary Member
- Posts: 1153
- Joined: Wed Jun 20, 2007 6:21 am
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If a and b are divisible by n then a-b & a+b both will be divisible by n.
Explanation:
lets say a= 5, b = 25, then a-b & a+b will always be a multiple of 5
5-25 = -20 is a multiple of 5
5+25 = 30 is a multiple of 5
Lets say a=28, b=14 both are multiples of 2 and 7
Therefore,
28-14 = 14 is a multiple of 2 and 7
28+14 = 42 is a multiple of 2 and 7
Now coming to the statement II
Lets say n+6 = X
X is a multiple of 3
6 is a multiple of 3
X is a multiple of 3
Therefore n has to be a multiple of 3
Hope its clear. Let me know if you still have any questions.
Explanation:
lets say a= 5, b = 25, then a-b & a+b will always be a multiple of 5
5-25 = -20 is a multiple of 5
5+25 = 30 is a multiple of 5
Lets say a=28, b=14 both are multiples of 2 and 7
Therefore,
28-14 = 14 is a multiple of 2 and 7
28+14 = 42 is a multiple of 2 and 7
Now coming to the statement II
Lets say n+6 = X
X is a multiple of 3
6 is a multiple of 3
X is a multiple of 3
Therefore n has to be a multiple of 3
Hope its clear. Let me know if you still have any questions.