Question

a two digit number is 4 times the sum of its digits if 18 is added to the number the digits are reversed find the number​

Answer 1

Answer:

The required number is 24.

Step-by-step explanation:

Let the unit digit of the number be y

the ten's digit be x.

Then the two-digit number will be given by

10x + y

According to the question;

10 x + y = 4 (x + y) 

or, 10 x + y = 4x + 4y

or,  6x = 3y

 so,  y = 2x ____________(1)

Also, after adding 18 the digits got reversed

so, ( 10x + y ) + 18 = 10y + x

or, 10x + y - 10y - x = 18

or, 9y – 9x = 18 _________(2)

Substitute the value of y in eqn (2)

18x – 9x = 18

or, 9x = 18

so, x = 2

Therefore, y = 2x = 2x2 = 4

Hence, the number obtained is 10x + y

= 10x2 + 4

= 24