If x is an integer and y = 3x + 2, which of the following CANNOT be a divisor of y ?
(A) 4
(B) 5
(C) 6
(D) 7
(E) 8
I dont understand how C is the answer?
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Ans - C
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Dividend and divisor problem?
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pepeprepa
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C is the answer because other answers can be a divisor of y. If you can divide y by all the proposals except one, so this one is the answer: they ask you "which one CANNOT be a divisor of y".
A) 3*2+2=8 divisible by 4
B) 3*6+2=20 divisible by 5
D) 3*4+2=14 divisible by 7
E) 3*2+2=8 divisible by 8
A) 3*2+2=8 divisible by 4
B) 3*6+2=20 divisible by 5
D) 3*4+2=14 divisible by 7
E) 3*2+2=8 divisible by 8
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Or you can look at it this way:prees20 wrote:If x is an integer and y = 3x + 2, which of the following CANNOT be a divisor of y ?
(A) 4
(B) 5
(C) 6
(D) 7
(E) 8
I dont understand how C is the answer?
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Ans - C
If y = 3x + 2, then y is two larger than a multiple of 3. That is, the remainder is 2 when you divide y by 3. So y is not divisible by 3.
If y isn't divisible by 3, y definitely is not divisible by 6.
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malolakrupa
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For a number to be divisible by 6 it needs to be a divisible by 2 and 3 both . 3 times any number + 2 could be divisible by 2 and not by 3 . Hence 6 is the only divisor in the list.
