the same way you would do normal subtraction you just have to line your decimals and subtract normally, and any places that don't have a number could be filled with a 0
To solve decimal subtraction problems, you just solve it as a normal subtraction problem. Once you find you answer, count how many numbers are to the right of the decimals you are subtracting. If there was two digits on the right of decimal point for the first number and three digits to the right of the decimal point for the second number (a total of 6) then you would place the decimal 6 places to the right for the final answer.
there are 11 paintings and 9 paintbrushes, added together you have a total of 20 items. There are 9 paintbrushes and 20 items in total which is 9/20. 9/20 as a percentage is 45%
