Question

A number consist of tow digits whose sum is 8.if 18is added to the number it's digits are reversed find the number

Answer 1

Let the digit in the tens place be x and that of units place be y.
The original number is 10x + y.
The number obtained after reversing the digits is 10y + x.

As per the first condition,
x + y = 8                   (eq no 1)

As per the second condition,
10x + y + 18 = 10y + x
10x - x - 10y + y + 18 =0
9x - 9y = -18
x - y = -2                    (eq no 2)[Dividing throughout by 9]

Adding eq no 1 and eq no 2
x + y = 8
x - y = -2
2x = 6
x = 3

Substituting x = 3 in eq no 1
3 + y = 8
y = 5

The original number = 10x + y
=10(3) + 5
= 30 + 5
= 35

The number is 35.

You can verify it like this:
35 + 18 = 53
The digits are reversed.

Answer 2

Answer:

35

Step-by-step explanation:

3+5=8(the sum of the digits is 8)

35+18=53(the numbers are being reversed)

so the number is 35.