# If 27 is added to the number, digits are reversed, the number is :

The sum of two digits of a number consisting of two digits is 7. If 27 is added to the number, digits are reversed, the number?

- 25
- 52
- 34
- 43

**Answer: (1) 25 **

**Explanation:-**

Let the digits be X and Y.

The sum of two digits of a number consisting of two digits is 7.

Then, X + Y = 7 …………………………. (1)

If 27 is added to the number, digits are reversed,

Then, 10 X + Y = 27 + 10 Y + X

9 X – 9 Y = 27 …………………………… (2)

Multiply by 9 in equation (1),

Then, 9 X + 9 Y = 63 ………………….. (3)

Add equation (2) & (3),

9 X + 9 X – 9 Y + 9 Y = 27 + 63

18 X = 90

X = 90/18

X = 5

Put the value of X = 5 in equation (1),

Then , 5 + Y= 7

Y = 7 – 5

Y = 2

Then, the number is 25.

Hence, the answer is (1) 25.