Question

digits of two digit differ bythe digits of two digit differ by 3 if the digits are interchanged and the resulting number is added to the original number we get 121 find the original number ​

Answer 1

Answer:

74

Step-by-step explanation:

Let x be the number at tens place.

And y be the number at unit place.

So the original number = 10x+y - - - - - (a)

Now, according to the ques,

x-y =3

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

When the digits are interchanged, the number becomes 10y+x

So,

10y+x + 10x+y = 121

=> 11x + 11y = 121

=> 11(3+y) +11y =121 [from (1)]

=> 33 + 11y + 11y= 121

=> 22y = 121-33

=> 22y = 88

=> y = 88/22

=> y= 4

Substituting this in eq (1),

x= 3+y

=> x= 3+4

=> x= 7

So, x=7 and y=4

In eq (a),

The original number = 10x +y

= 10(7) +4

= 70 +4

= 74

So, the original number was 74.