6 containers have paint in them.
Step-by-step explanation: Firstly we must convert them to similar fractions, so times the denominator of each fraction by the denominator and numerator of the other fraction (the denominator is the bottom number and the numerator is the top number.) So 3 times 1 is 3, 3 times 8 is 24, so the fraction of paint poured into each container changes to 3/24. 8 times 2 is 16, 8 times 3 is 24, so the total amount of paint poured is 16/24, divide the numerator of paint poured by the numerator of paint in each container, so 16 divided by 3, you get 5 remainder 1, the remainder 1 still counts as part of the next container so 6 container have paint in them.
Hope this helps.