If x, y, and z are non-negative integers, is 5(x + y) + z divisible by

Question

If x, y, and z are non-negative integers, is 5(x + y) + z divisible by 5?

(1) (x + y) is a multiple of 5.

(2) z is divisible by 5

Archit3110 · Answer

target is 5(x + y) + z divisible by 5
where value of x,y,z can be 0,1,2,3....
#1
(x + y) is a multiple of 5.
z is not know so insufficient 
#2
z is divisible by 5
z= 5*a where a is multiple of factor with which z is divisible 
so we get
5*(x+y)+5*a /5 or say 5 *  /5 
which is yes ; sufficient

OPTION B

IanStewart · Answer

5(x + y) is a multiple of 5. If we add z to it, the result will only be a multiple of 5 if z itself is a multiple of 5. So Statement 2 is sufficient, and Statement 1 is irrelevant, and the answer is B.

Tonkotsu · Answer

Without looking at the 2 statements we can notice, first, that the question is asking whether

z is divisible by 5: 5*(x + y)/5 + z/5.

1) does not help us solve this problem because we already know that, regardless of (x+y) being divisible by 5, that 5*(x+5) yields an integer.

2) answers our question that z contains a factor of 5.  Sufficient

AritraKundu · Answer

Analyze the question stem

For any number to be divisible by 5, the units digit have to be 0 or 5
Here, 5(x+y)+z= should give the resultant with units digit 0 or 5 (to be divisible by 5)
5*any value should give units digit 0 or 5. So we know the units digit of 5(x+y) is 0 or 5
So we just have to figure out the units digit of z

Statement 2 exactly gives us that input

Answer: B

If x, y, and z are non-negative integers, is 5(x + y) + z divisible by

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