Dividing decimals: 
Lets use an example, 0.5/0.2
To make things easier, multiply both the numerator and the denominator by a number that will result in integers / whole numbers 
0.5 (10) / 0.2 (10) 
5/2 
5/2 is THE SAME AS 0.5/0.2 
5/2 = 2.5 so 0.5 / 0.2 = 2.5
Multiplying: 
Example:
 0.5 x 0.2 
Count the TOTAL number of decimal places. In this case it is 2. Now ignore the decimal points and do 5 x 2 = 10.
The total number of decimal places you counted before was 2. 
Now move those two decimals back in 10. 
0.1
Hope this helped!