[tex]\[
(A \text{ or } B) = P(A) + P(B) - P(A \text{ and } B)
\][/tex]

Sarah has 52 balloons; 13 of the balloons are red, and 4 of the balloons have polka dots. Just 1 of the red balloons has polka dots.

What is the probability of randomly choosing a balloon that is either red or has polka dots?

A. [tex]\(\frac{2}{13}\)[/tex]

B. [tex]\(\frac{4}{13}\)[/tex]

C. [tex]\(\frac{17}{52}\)[/tex]

D. [tex]\(\frac{9}{26}\)[/tex]



Answer :

To determine the probability of randomly choosing a balloon that is either red or has polka dots, we need to use the formula for the union of two events:

[tex]\[ P(\text{Red or Polka Dot}) = P(\text{Red}) + P(\text{Polka Dot}) - P(\text{Red and Polka Dot}) \][/tex]

Here's a step-by-step solution to the problem:

1. Total number of balloons:
[tex]\[ 52 \][/tex]

2. Number of red balloons:
[tex]\[ 13 \][/tex]
Therefore, the probability of selecting a red balloon is:
[tex]\[ P(\text{Red}) = \frac{13}{52} = 0.25 \][/tex]

3. Number of polka dot balloons:
[tex]\[ 4 \][/tex]
Therefore, the probability of selecting a polka dot balloon is:
[tex]\[ P(\text{Polka Dot}) = \frac{4}{52} = \frac{1}{13} \approx 0.0769 \][/tex]

4. Number of balloons that are both red and have polka dots:
[tex]\[ 1 \][/tex]
Therefore, the probability of selecting a balloon that is both red and has polka dots is:
[tex]\[ P(\text{Red and Polka Dot}) = \frac{1}{52} \approx 0.0192 \][/tex]

5. Applying the formula for the union of the two events:
[tex]\[ P(\text{Red or Polka Dot}) = P(\text{Red}) + P(\text{Polka Dot}) - P(\text{Red and Polka Dot}) \][/tex]

Substituting the calculated probabilities:
[tex]\[ P(\text{Red or Polka Dot}) = 0.25 + 0.0769 - 0.0192 = 0.3077 \][/tex]

6. Converting the decimal probability back to a fraction (if required for the multiple-choice options):
[tex]\[ 0.3077 \approx \frac{16}{52} = \frac{4}{13} \][/tex]

Therefore, the probability of randomly choosing a balloon that is either red or has polka dots is [tex]\( \frac{4}{13} \)[/tex].

The correct answer is:
[tex]\[ \boxed{\frac{4}{13}} \][/tex]