Question

The digits of a two digit number differ by 3 .If the digits are interchanged and added to the original number we get 121. Find the original number ?
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Answer 1

Answer:

One’s place => 7

Tens place => 4

Step-by-step explanation:

Let digit in one’s place be ‘x’ and tens place be ‘y’.

x-y=3

Original number => 10x+y

When digits are interchanged=> 10y+x

According to given statement,

10x+y + 10y+x = 121

11(x+y) = 121

x+y = 11

x+y = 11. So y = 11-x

x-y = 3

x-(11-x) = 3

x-11+x = 3

2x = 3+11

So, x=7

Digit in one’s place is 7 and tens place is 4