Question

The sum of the digits of a two digit number is 15 the unit digit is one less than tens digits find the number

Answer 1

Answer:

Let the digit at the unit place be x.

Then, the digit in the tens place =(15−x)

∴ Original number =10×(15−x)+x=150−9x

On reversing the digits, we have x at the tens place and (15−x) at the unit place.

∴ New number =10x+(15−x)=(9x+15)

According to the given condition,

(Original number) − (New number) =27

⇒(150−9x)−(9x+15)=27

⇒150−9x−9x−15=27

⇒135−18x=27

⇒18x=135−27

⇒x=(

18

108

)=6

∴ In the original number, we have units digit =6 and tens digit =(15−6)=9

Hence, the original number is 96.