SOLUTION: if the integer n is divided by 7,the remainder is 2.what is the remainder if 5n is divided by 7 ? a 0 b 2 c 3 d 4 e 5

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Question 300863: if the integer n is divided by 7,the remainder is 2.what is the remainder if 5n is divided by 7 ?
a 0 b 2 c 3 d 4 e 5
Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
n%2F7=q%2B2%2F7
where n,q are integers.
Multiply both sides by 7.
n=7q%2B2
5n=35q%2B10
5n%2F7=35q%2F7%2B10%2F7
5n%2F7=5q%2B7%2F7%2B3%2F7
5n%2F7=%285q%2B1%29%2B3%2F7
5q%2B1 is also an integer.
The remainder is then 3.
c) 3.