Question

The unit digit of a two digit number is 3 and seven times the sun of the digit is the number itself . find the number

Answer 1

let number be 10x+y
where y is the unit digit
y=3(given)

A/Q

7(x+y) = 10x + y
=> 7x + 21 = 10x + 3
=> 3x = 21- 3
=> 3x = 18
=> x = 6

thus number is
10× 6+ 3
= 63 answer