Multiple Choice Question (MCQ)
When the positive integer m is divided by 7, the remainder is 4. What is the remainder when 2m is divided by 7 ?
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0
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1
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4
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6
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8
When the positive integer m is divided by 7, the remainder is 4. What is the remainder when 2m is divided by 7 ?
0
1
4
6
8
If m is divided by 7, the remainder is 4
m = 7q+4 (q is positive integer)
Then
2m = 2(7q+4) = 14q+8
When divided by 7,
\dfrac{2m}{7} = \dfrac{14q+8}{7} = 2q+1+\dfrac{1}{7}
Therefore the remainder is 1
For example, 11 is divided by 7, the remainder is 4. When 22 is divided by 7, the remainder is 1.
B is correct