Question

a number consists of two digit number is 7 times the sum of the digits 27 is subtracted from the number the digits are reversed find the number

Answer 1

Hey

Here is your answer,

Let x is the tenth digit and y is unit digit.
then the number is 10x+y.

The number is 7 times the sum of the digits. So,
10x+y = 7(x+y)
⇒10x-7x = 7y-y
⇒3x = 6y
⇒x=2y

Also (10x+y)-27 = 10y+x
⇒10x-x = 10y-y+27
⇒9x = 9y +27
⇒9×2y = 9y + 27
⇒18y - 9y = 27
⇒9y = 27
⇒ y = 27/9 = 3
x = 2y = 6

The number is 10x+y = 63

Hope it helps you!