the probability that a professional baseball player will get a hit is 1/3. Calculate the exact probability that he will get at least 3 hits in 5 attempts.

Question

anonymous · Answer

that was wrong, sorry

anonymous · Answer

at least 3 means 
3 or 4 or 5
you have to compute each of these and add them up

anonymous · Answer

exactly 3 is 
$$P(x=3)=\binom{5}{3}\left(\frac{1}{3}\right)^3\left(\frac{2}{3}\right)^2$$
meaning 3 hits, 2 not hits, and $\binom{5}{3}=\frac{5\times 4}{2}=10$ ways to get order the three hits and two not hits

anonymous · Answer

The answer has to be the exact probability so shouldnt it be written differently?

anonymous · Answer

yeah you have to actually compute that number, and then do it again for $P(x=4)$ and $P(x=5)$

anonymous · Answer

$$P(x=4)=\binom{5}{4}\left(\frac{1}{3}\right)^4\left(\frac{2}{3}\right)$$and 
$$P(x=5)=\left(\frac{1}{3}\right)^5$$

anonymous · Answer

For the answer i got 17/81
correct?