What will be the remainder of: 12345678910/8

Question

A. 4
B. 5
C. 6
D. 3

PS: Apart from time consuming traditional Division method, is there any trick to attempt such type of questions?

Bunuel · Accepted Answer

You can do the same by breaking 12345678910 only into two parts: 12345678910 = 12345678000 + 910.

12345678000 is divisible by 8, because it ends with 000 and the remainder when 910 is divided by 8 is 6.

Answer: C.

mau5 · Answer

For any # to be divisible by 8, the last 3 digits of that # should be divisible by 8

Given # --> 12345678910 -->  10^{10}+2*10^9+.... 8000+910

All the numbers above are divisible as they all end in 000. Thus, the remainder is what is obtained by \frac{910}{8} = 6

C.

TeamGMATIFY · Answer

This question tests the divisibility rules:
 2 - The last digit should be even
3 - Sum of the digits should be multiple of 3
4 - Last two digits should be divisible by 4
5 - Last digit should be 5 or 0
6 - Number is even and if the sum of its digits is divisible by 3
7 - Quiet complex and should not be used
8 - Last three digits should be divisible by 8
9 - Sum should be divisible by 9

Taking the last 3 digits 12345678910 
Remainder of 910/8 = 6
Option C

Abhishek009 · Answer

\frac{12345678910}{8}  = \frac{12345678000}{8}  +  \frac{910}{8}

\frac{12345678000}{8}  +  \frac{910}{8}  =   abcd1   +  113  +  \frac{6}{8} 
  
So, Remainder is (C) 6

Sumitj2016 · Answer

Any number is divisible by 8 only if its last 3 digit is divisible by 8. here we will divide 910 by 8 we get 6 as remainder. Hope it helps!

JeffTargetTestPrep · Answer

When dividing by 8, we can use the rule that if the last 3 digits of a number are divisible by 8, then that number is divisible by 8.

For example, 110,440 is divisible by 8, since 440 is divisible by 8.

Furthermore, the remainder when a number is divided by 8 is the same as the remainder when the last 3 digits of the number are divided by 8.

So, to determine the remainder when 12345678910 is divided by 8, we simply divide 910 by 8:

910/8 = 113 remainder 6

Answer: C

AqsaGhori · Answer

I took last three digit keeping in view "A number is divisible by 8 if its last three digits are divisible by 8"
when I divide 910 got 904 so 6 is remainder
Option C
Expert opinion please will it satisfies all condition??
TIA

Bunuel · Answer

Yes. It's the same exact approach used in above solutions.

shashankism · Answer

Any number divisible by 8 will have last 3 digit also divisible by 8.
So, we should check the remainder of 910/8 = 6

Answer C

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What will be the remainder of: 12345678910/8

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