Question

the sum of digit of two digit no is 10 the no is decreased by 36 if digit are reversed find no.

Answer 1

Let the tens place digit be a
And Unit place digit be b

Number = 10a + b

Reversed number = 10b + a

Sum of digits = a+b

=> a+b = 10

=> a = 10 - b --------(1)

Now,

10a+b - 36 = 10b + a

=> 10a +b - 10b - a = 36

=> 9a - 9b = 36

=> a-b = 4

=> 10-b-b = 4 (using equation 1)

=> 10-2b = 4

=> 2b = 10 - 4

=> 2b = 6

=> b = 3

Now, on putting the value of b in equation 1, we get

a= 10-b

a= 10-3

a= 7

Required number = 73