well, Mark has
1 1/3 of yellow paint
1 1/4 of green paint and
7/8 of blue paint
now, bear in mind, the yellow is a bucket and 1/3 more, the green one is one bucket and 1/4 more and the blue is 7/8 which is almost 8/8, so is almost a bucketfull.
Then he's going to use 3/4 of each, so, we'd have to subtract 3/4 from each, and there'll be some left still in the paint bucket.
How many will he have left altogether? well, we simply add the leftovers.

