Discussion of Question with ID = 079 under Problems-on-Numbers

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Question

x should be replaced by which minimum number so that 77x7533423 is completely divisible by 3?

A

1.

B

2.

C

4.

D

3.

Soln.
Ans: a

If the above number has to be divisible by 3, the sum of the digits, i.e., 7 + 7 + x + 7 + 5 + 3 + 3 + 4 + 2 + 3, should be divisible by 3. So we can see that $x + 41$ should be divisible by 3. By inspection, x = 1.


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