The tens digit of a two-digit number is twice the unit digit. If the digits are reversed, the new number is 36 less than the original number. Find the number

The original number is 84.

Step-by-step explanation:

Let the number be xy.

Then x = 2y.

The numerical value of xy is 10x + y,

so 10y + x = 10x + y - 36.

9y - 9x = - 36

y - x = - 4

Substitute for x in the above equation:

y - 2y = - 4

-y = - 4

So y = 4

and x = 2y = 8.

The number is 84

Step-by-step explanation:

x = unit digit

10 (2 x) + x = 10 x + 2 x + 36

9 x = 36

x = 4 (4 is the unit digit, which is half of the tens digit, so the tens digit is 8)

Number is 84

The reverse of 84 is 48

48 is 36 less than 84

84 = 48 + 36