Question

Solve the following:

Find the least value that must be given to number a so that the number 91876a1 is divisible by 3.

Answer 1

Given, 91876a1 is divisible by 3.
Since, we know that, if a number is divisible by 3, then the sum of the digits is a multiple of 3.
So, 9 + 1 + 8 + 7 + 6 + a + 1 = 32 + a is divisible by 3.
Here, a can take values from 0 to 9.
But the least number is to make 32 + 1 = 33, a multiple of 3
Hence, the minimum value of a is 1 to make 91876a2 divisible by 3.