Question

A two digit number is 4 times the sum of its digits.if 27 is added to the number the digits are reversed.find the number.

Answer 1

$10x + y = 4x + 4y \\ 6x = 3y \\ 2x = y \\ now \\ 10x + y + 27 = 10y + x \\ 9y - 9x = 27 \\ y - x = 3 \\ using \: y = 2x \\ 2x - x = 3 \\ x = 3 \\ y = 2x = 6 \\ number = 36$

Answer 2

Answer:

hey!

Step-by-step explanation:

--=============================================

Let tens digit be x and units digit be y

Then number =10x+y

Since the number is 4 times the sum of digits

Hence 10x+y=4(x+y) i. e. 6x=3y. Or 2x=y……(i)

Also when 27 is added the digits are reversed

Number when digits are reversed =10y+x

Hence 10x+y+27=10y+x

9x+27=9y. Or x+3=y………..(ii)

From (i) and (ii) we get

x+3=2x hence x=3. and y=2x=6

and number =36