Question

please answer this question

Answer 1

Hey there !

Solution:

Let the two digits be x and y

=> x + y = 7   => Equation 1

Also let the original number be 10x + y

Now the number obtained while reversing is 10y + x

It is given that number obtained by interchanging digits is 27 more than the original number.

=> 27 + 10x + y = 10 y + x

=> 27 = 10y - y + x - 10x

=> 27 = 9y - 9x

Dividing by 9 throughout the equation we get,

=> 3 = y - x    => Equation 2

Solving Equation 1 and Equation 2,  we get,

y + x = 7

y - x = 3

________

2y = 10

_________

=> y = 10 / 2 = 5

=> y - x = 3

=> 5 - x = 3

=> 5 - 3 = x

=> x = 2

Hence x = 2, y = 5

Therefore Original Number = 10x + y

=> 10 ( 2 ) + 5

=> 20 + 5

=> 25

Hence the original number is 25.

Hope my answer helped !