Question

the digits of a two digit number differ by 3. if the digits are interchange, and the resulting number is added to original number, we get 143. what is original number ​

Answer 1

Answer:

let the digit at ten's place be X

digit at one's place be y.

According to question:-

x-y=1....(1)

original number:10x+y

reversed number:10y+X

According to the question:-

10x+y+10y+x=143

11x+11y=143

11(x+y)=143

x+y=143/11

x+y=13.....(2)

Adding (1) and (2)

x+y=13

x-y=3

2x=16

x=8

y= 5

Original number= 10*8+5=85

Answer 2

Here's the Solution :

Let the digits of the two digit number be x and y .

Therefore , the number is

10x + y

According to Question :

x-y = 3 ----->(1)

And ,

10x + y + 10y + x = 143

=> 11x + 11y = 143

=> 11( x + y ) = 143

=> x + y = 13 ---(2)

Adding (1) and (2) we have :

x- y + x + y = 3 + 13

=> 2x = 16

=> x = 8

Using x = 8 in (1) we have

8 - y = 3

=> -y = 3-8

=> -y = -5

=>y = 5

Therefore, the required number is

10×8+5

=80+5

=85