Question

The sum of a tow digit number is 7.on interchaging the number exceeds original number by 27

Answer 1

let the 1st no be and

second no be y

according to the question,

x+y=7 -------------- 1

on interchanging the digits we get,

10y+x=10x+y+27

10y-y+x-10x=27

9y-9x=27

9(y-x)=27

y-x = 27/9

y-x=3

-x + y = 3 ----------- 2

from eq 1 and 2

x+y=7

+(-x+y=3)

--------------

2y=10

y=10/2

y=5

now we can substitute the value of y in eq 1

x+y=7

x+5=7

x=7-5

x=2

hence the no is 25

hope my ans is helpful :)