Answer: B. 11%
Step-by-step explanation:
Let A = Event that students eat breakfast in the morning.
B= Event that students floss their teeth.
We are given P(A)=57%=0.57
P(B)=80%=0.80
P(A∩B) = 46% =0.46
Now, the probability that a student from this class eats break feast but does not floss their teeth :-
[tex]P(A-B)=P(A)-P(A\cap B)\\\\ = 0.57-0.46=0.11=11\%[/tex]
Hence, the probability that a student from this class eats break feast but does not floss their teeth= 11%