Combining the tennis and soccer balls, there are 15+5=<<15+5=20>>20 balls in each basket
There are 5 baskets, hence 5*20=<<5*20=100>>100 balls in total
3 students removed 8 balls each, they removed 3*8=<<3*8=24>>24 balls
From the total number of balls, they left 100-24=<<100-24=76>>76 balls
There are 56 balls left so the other 2 students must have removed a total of 76-56=20 balls
This means that each of these 2 students removed 20/2=<<20/2=10>>10 balls.
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