Question

sum of the digit of a 2-digit is 6.When we interchange the digits,the resulting new number is less than the original number by 18 .What is the 2- digit number?​

Answer 1

Answer:

Let tenth digit of an original number be x & unith digit be y so  

original number would be  

                                    10x+y

when digits are reversed new number would be x+10y

 

10x+y = x+10y+18

9x -9y =18

x-y=2.....eqn 1

 

sum of digits is 6 so

                                   x+y=6..... eqn 2

adding eqn 1 & 2, we get 2x = 8

                                     x=4

                                     y=2

 

Original number =42