For two programs at a university, the type of student for two majors is as follows.

\begin{tabular}{|c|c|c|c|}
\hline
& History & Science & Total \\
\hline
Undergraduate & 390 & 422 & 812 \\
\hline
Graduate & 73 & 188 & 261 \\
\hline
Total & 463 & 610 & 1073 \\
\hline
\end{tabular}

Find the probability that a student is an undergraduate student, given they are a science major.

[tex]\[
P(\text{undergrad} \mid \text{science}) = \frac{P(\text{undergrad and science})}{P(\text{science})} = [?]
\][/tex]

Round to the nearest hundredth. [tex]$\square$[/tex]



Answer :

To find the probability that a student is an undergraduate student given that they are a science major, we use the concept of conditional probability. The conditional probability \( P(A \mid B) \) is given by:

[tex]\[ P(A \mid B) = \frac{P(A \cap B)}{P(B)} \][/tex]

Here, we are interested in finding the probability that a student is an undergraduate given that they are a science major. Let:
- \( A \) be the event that a student is an undergraduate.
- \( B \) be the event that a student is a science major.

According to the table, we have:

- The number of undergraduate science students (event \( A \cap B \)): 422
- The total number of science students (event \( B \)): 610

So, the conditional probability \( P(\text{undergrad} \mid \text{science}) \) is:

[tex]\[ P(\text{undergrad} \mid \text{science}) = \frac{\text{Number of undergraduate science students}}{\text{Total number of science students}} = \frac{422}{610} \][/tex]

Calculating this division, we get:

[tex]\[ \frac{422}{610} \approx 0.6918032786885245 \][/tex]

Rounding this result to the nearest hundredth, we get:

[tex]\[ 0.69 \][/tex]

Therefore, the probability that a student is an undergraduate given that they are a science major is approximately [tex]\( 0.69 \)[/tex].