Question

The sum of the digit of a two digit number is 7 . the number obtained by interchanreasing the digit exceeds the
original number by 27 find the number

Answer 1

Answer:

let the units place be x

then the tens digit be 7 - x

number formed by these digits = 10 x t's digit+u's digit

=> 10(7-x)+x

70 x -10 x +x

70 x -9x

when the digits are interchanged than,

t's digit= x

u's digit = 7-x

the new no. formed = 10x + 7-x

= 9 x +7

given that the no. exceeds by 27

new no. - given no.

9x +7 - (70-9x)=27

9 x + 7 - 70 + 9x =27

18x -63= 27

18 x = 63+27

18 x= 90

x = 90/18

=5

the no. = 70- 9x 

=> 70-45

=> 25

hope it will help u