Question

If x is a digit such that the number 18x71 is divisible by 3, find possible values of x

Answer 1

Solution:-

As we know that number are divisible by 3 if the sum of all the individual digits is evenly divisible by 3.
Given number = 18x71
The sum of all the digits of 18x71
= 1 + 8 + 7 + 1 
= 17
17 is not divisible by 3, so we need 18, that is divisible by 3.
17 + 1 = 18
So, the values of x are 1, 4 and 7.
And, the numbers are 18171, 18471 and 18771
Answer.

Answer 2

The number 18x71 is divisible by if the sum of its digits is divisible by 3.
1+8+7+1=17
now, 17+1=18 divisible by 3.
17+4=21 divisible by 3.
17+7=24 divisible by 3
Therefore the values of x are 1,4 and7 and the numbers are 18171, 18471 and 18771.