If the number x3458623y is divisible by 88, what is the

Question

If the number x3458623y is divisible by 88, what is the value of x?

A. 1
B. 2
C. 3
D. 4
E. 5

Bunuel · Accepted Answer

Since x34,586,23y is divisible by 88=8*11 then it's divisible by both 8 and 11. Now, in order a number to be divisible by 8 its last three digits must be divisible by 8 , so 23y must be divisible by 8. That's only possibly if y=2 --> 232/8=29. So, our number is x34,586,232. Next, in order a number to be divisible by 11 the difference between the sum of the odd numbered digits (1st, 3rd, 5th...) and the sum of the even numbered digits (2nd, 4th...) must be divisible by 11 . So, (x+4+8+2+2)-(3+5+6+3)=x-1 must be divisible by 11, which means that x can only be 1. Answer: A. For more on divisibility check Number Theory chapter of Meth Book: math-number-theory-88376.html Hope it helps.

Bunuel · Answer

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kpali · Answer

x3458623y is divisible by 88 so, it should be divisible by 8 and 11

x+14+y -17 = n * 11
x+y-3 = n*11
n cant be 2, as in that case RHS will become 22, and on LHS the max we can get is 9+9-3 = 15
 
so n=0 or 1

now it should be divisible by 8 also, so 23y should be divisible by 8
240 is perfectly divisible by 8, so the no less then that will be 232

thus, y=2

now, x+2-3 =n*11
x-1=n*11

now n=1 is also not possible as lhs max can only be 9-1 =8

thus, n=0
hence, x=1

Ans: A

cumulonimbus · Answer

to be divisible by 11:

3+5+6+3=2+y+8+4+x
3=x+y

x y 
3 0 - not correct (not divisible by 4)
0 3 - not correct (not divisible by 2) 
2 1 - not correct (not divisible by 2)
1 2 - correct (divisible by 4) - (...232) - is divisible by 4

PareshGmat · Answer

Did in the same way, however considered last three digits   23y   for divisibility check with 8

bumpbot · Answer

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If the number x3458623y is divisible by 88, what is the

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If the number x3458623y is divisible by 88, what is the

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