Since the probability of a hit is 2/5, not getting hit has the probability
(1-2/5)=3/5.
We deduce that the probability of the event:
"that it will take at least three times at bat for him to get a hit" is the following:
[tex]\left( \frac{3}{5}\right)^3 \left( \frac{2}{5}\right)^7 =[/tex]