What is the value of the two-digit positive integer n?
(1) The sum of the digits in n is 12.
(2) If the digits in n are reversed, the value of the number formed is 36 more than the value of n.

Respuesta :

Value of n is 48

Step-by-step explanation:

Let the two digit number n be ab, where a and b less than 10 and greater than 0.

The sum of the digits in n is 12

That is

                        a + b = 12 --------------------------eqn 1

If the digits in n are reversed, the value of the number formed is 36 more than the value of n

                       ba - ab = 36 ----------------------eqn 2

Let us check all the cases satisfying eqn 1 satisfies eqn 2 also

If a = 1, b is 11 which is not possible

If a = 2, b is 10 which is not possible          

If a = 3, b is 9 which is possible

         Substituting in eqn 2

                       ab = 39 and ba = 93

                        93 - 39 = 54 ≠ 36    

          Not correct  

If a = 4, b is 8 which is possible

         Substituting in eqn 2

                       ab = 48 and ba = 84

                        84 - 48 = 36    

          Correct.

Value of n is 48