Question

the sum of the digit of a two digit number is 9.if 9 is added to the number the digits interchange their places find the number

Answer 1

★ Ello ★

here is your answer !!

let the number be x and y

x + y = 9 ---------------------(1)

unit digit be y

ten' s digit be y

10x + y


number interchange is

10 y + x



according to question !!


=> 10 x + y + 9 = 10 y + x

=> 9 ( x - y ) = -9

=> x - y = -1 --------------------(2)

from equation 1 and 2 we get


x + y = 9
x -y = -1
=====
2x = 8

x = 4


putting the value of x we get

y = 5


hence ,.


the number formed is => 10x + y

10 × 4 + 5


=> 45


hence the number formed is

★ 45 ★


hope it helps you dear !!


$thanks$