Answer:
Step-by-step explanation:
total number of students=21
students play neither sport=6
students who play at least one sport=21-6=15
Let play basketball=X
and play baseball=Y
n(XUY)=n(X)+n(Y)-n(X∩Y)
15=11+6-n(X∩Y)
n(X∩Y)=17-15=2
reqd. probability=2/21