To calculate the probability of selecting a student who either wants the option to keep studying online or is a boy, we can use the principle of inclusion-exclusion.
Let:
- \( P(A) \) = probability that a student wants the option to keep studying online = \( \frac{13}{25} \)
- \( P(B) \) = probability that a student is a boy = \( \frac{10}{25} \)
- \( P(A \cap B) \) = probability that a student is both a boy and wants the option to keep studying online = \( \frac{3}{25} \)
Using the formula for the probability of either event occurring, we have:
\[ P(A \cup B) = P(A) + P(B) - P(A \cap B) \]
Substituting the values:
\[ P(A \cup B) = \frac{13}{25} + \frac{10}{25} - \frac{3}{25} \]
Based on the provided options, the correct mathematical sentence to calculate the probability is:
Start Fraction 13 over 25 End Fraction plus Start Fraction 10 over 25 End Fraction minus Start Fraction 3 over 25 End Fraction.