The distribution of pitches thrown in all the at-bats in a baseball game is as follows.

\begin{tabular}{|c|c|c|c|c|c|}
\hline
Pitches & 1 & 2 & 3 & 4 & 5 \\
\hline
Frequency & 12 & 16 & 32 & 12 & 8 \\
\hline
\end{tabular}

Find the probability that a pitcher will throw exactly 3 pitches in an at-bat.

[tex]\[ P(3) = [?] \][/tex]



Answer :

To find the probability that a pitcher will throw exactly 3 pitches in an at-bat, we can follow these steps:

### Step 1: Identify the frequencies and the total number of at-bats

From the table provided, the frequencies of pitches thrown are:
- 12 at-bats with exactly 1 pitch
- 16 at-bats with exactly 2 pitches
- 32 at-bats with exactly 3 pitches
- 12 at-bats with exactly 4 pitches
- 8 at-bats with exactly 5 pitches

### Step 2: Calculate the total number of at-bats

To find the total number of at-bats, we sum up all the frequencies:

[tex]\[ 12 + 16 + 32 + 12 + 8 = 80 \][/tex]

So, the total number of at-bats is 80.

### Step 3: Identify the frequency of at-bats with exactly 3 pitches

From the table, we see that there are 32 at-bats where exactly 3 pitches were thrown.

### Step 4: Calculate the probability

The probability [tex]\( P(3) \)[/tex] that exactly 3 pitches are thrown in an at-bat is given by the ratio of the frequency of at-bats with exactly 3 pitches to the total number of at-bats:

[tex]\[ P(3) = \frac{\text{Frequency of 3 pitches}}{\text{Total number of at-bats}} = \frac{32}{80} \][/tex]

### Step 5: Simplify the fraction

[tex]\[ \frac{32}{80} = 0.4 \][/tex]

### Conclusion

The probability that a pitcher will throw exactly 3 pitches in an at-bat is:

[tex]\[ P(3) = 0.4 \][/tex]