The sum of a two-digit number and the number obtained by reversing the

1.	The sum of a two-digit number and the number obtained by reversing the order of its digits is 121, and the two digits differ by 3. Find the number.
Answer» Let us consider, one’s digit of a two digit number = x and Ten’s digit = y Number is x + 10y By reversing the digits, One’s digit = y and Ten’s digit = x Number is y + 10x As per the statement, x + 10y + y + 10x = 121 11x + 11y = 121 x + y = 11 …(1) And, x – y = 3 …(2) On adding, we get 2x = 14 or x = 7 On subtracting (2) form (1), 2y = 8 or y = 4 Answer: Number = 7 + 10( 4) = 47 or 4 + 10( 7) = 4 + 70 = 74

The sum of a two-digit number and the number obtained by reversing the order of its digits is 121, and the two digits differ by 3. Find the number.

Answer»

Let us consider, one’s digit of a two digit number = x and

Ten’s digit = y

Number is x + 10y

By reversing the digits,

One’s digit = y and

Ten’s digit = x

Number is y + 10x

As per the statement,

x + 10y + y + 10x = 121

11x + 11y = 121

x + y = 11 …(1)

And,

x – y = 3 …(2)

On adding, we get

2x = 14 or x = 7

On subtracting (2) form (1),

2y = 8 or y = 4

Answer:

Number = 7 + 10( 4) = 47

or 4 + 10( 7) = 4 + 70 = 74