The difference between the digits of a two-digit number is 2. The ratio of the units' digit to the tens' digit is 2. Find the number.

let x - units 

    y - tens

y - x = 2  

y = 2 + x 

x/y = 2  ---> x /2+x =2

x = 4 + 2x

-x = 4

x = -4

y - x  =2

 y -(-4) = 2

y + 4 = 2

y = 2 -4

y = - 2

So the number is 24.