Question

If 42x5 is a multiple of 9 and x is a digit, then find the value of x.

Answer 1

✪ Question ✪

If 42x5 is a multiple of 9 and x is a digit, then find the value of x.

✪ Given ✪

42x5 is a multiple of 9 and x is a digit.

✪ To find ✪

The value of x.

✪ Rule ✪

A number is divisible by 9 if the sum of its digits is divisible by 9.

✪ Solution ✪

So,

4+2+x+5 must be divisible by 9

4+2+5 = 11, which is not divisible by 9.

We have to add a number to 11 so that it becomes divisible by 9.

But since 11 > 9, we have to take a number as the sum of all the digits which is greater than 11 and divisible by 9.

9 × 2 = 18, which is greater than 11 and divisible by 9.

So, the sum of the digits is 18.

According to condition,

4+2+x+5 = 18

↝x+11 = 18

↝x = 18-11

↝x = 7

✪ Hence ✪

x = 7

✪ Therefore ✪

The value of x is 7.

๑ Hope this helps you. ๑