Question

the sum of the digits of a two digit no. is 15 if the no. obtained by reversing the order of the digits of the given no. exceeds the given no. by 9 find the given no.
​

Answer 1

Step-by-step explanation:

Let the tens,unit digit of number be=x,y respectively

Here xy=10x+y

⇒x+y=15

Second condition :

⇒10y+x=9+10x+y

⇒9x−9y=−9

⇒x−y=−1

Add resultant equations ;

⇒2x=14

⇒x=7

⇒y=8

∴two digit number =78

Hope it helps