Question

if the sum of the digit of a two digit number is 9.if the digit are interchange,the new number fromed is less than 9 than the first number.find the number​

Answer 1

Answer:

Let the digits at tens place and ones place: x and 9−x respectively.

∴ original number =10x+(9−x)

=9x+9

Now Interchange the digits: Digit at ones place and tens place: x and 9−x respectively.

∴ New number: 10(9−x)+x

=90−10x+x

=90−9x

AS per the question

New number = Original number +27

90−9x=9x+9+27

90−9x=9x+36

18x=54

x=

18

54

x=3

Digit at tens place ⇒3 and one's place : 6

∴ Two digit number: 36