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Compound Events Quick Check
4 of 54 of 5 Items

Question
Use the table to answer the question.

Studying Online

This table presents the number of girls and boys who prefer or do not prefer studying online.
  Girls Boys Row total
Want the option to keep studying online 10 3 13
Don’t want the option to keep studying online 5 7 12
Column total 15 10 25
Which mathematical sentence can be used to calculate the probability of selecting a student who wants the option to keep studying online or is a boy?

(1 point)
Responses

1325+1025−325
Start Fraction 13 over 25 End Fraction plus Start Fraction 10 over 25 End Fraction minus Start Fraction 3 over 25 End Fraction

1325+1025
  Start Fraction 13 over 25 End Fraction plus Start Fraction 10 over 25 End Fraction

325
Start Fraction 3 over 25 End Fraction

1325×1025
  Start Fraction 13 over 25 End Fraction times Start Fraction 10 over 25 End Fraction
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1 answer

To find the probability of selecting a student who wants the option to keep studying online or is a boy, we can use the principle of inclusion-exclusion.

Here's how you can break it down:

  • Let A be the event that a student wants the option to keep studying online. The probability of A is \( P(A) = \frac{13}{25} \) because there are 13 students who want to keep studying online out of 25 total students.

  • Let B be the event that a student is a boy. The probability of B is \( P(B) = \frac{10}{25} \) because there are 10 boys out of 25 total students.

  • The intersection of events A and B, denoted as \( P(A \cap B) \), is the probability of selecting a student who is both a boy and wants to keep studying online. There are 3 boys who want the option, so \( P(A \cap B) = \frac{3}{25} \).

Using the inclusion-exclusion principle, the probability of selecting a student who wants to keep studying online or is a boy is:

\[ P(A \cup B) = P(A) + P(B) - P(A \cap B) \]

Substituting the values we calculated:

\[ P(A \cup B) = \frac{13}{25} + \frac{10}{25} - \frac{3}{25} \]

Therefore, the mathematical sentence that can be used is:

\[ \frac{13}{25} + \frac{10}{25} - \frac{3}{25} \]

So, the correct answer is: 1325+1025−325 Start Fraction 13 over 25 End Fraction plus Start Fraction 10 over 25 End Fraction minus Start Fraction 3 over 25 End Fraction.