Answer:
6/20 = 3/10
Explanation:
Her brother gets the first treat. There are 2 grape treats out of 3+2 = 5 total; this is a probability of 2/5.
Maggie gets the second treat. There will still be 3 cherry treats left, but only 5-1 = 4 treats remaining; this is a probability of 3/4.
Together this gives us 2/5(3/4) = (2*3)/(5*4) = 6/20 = 3/10