Question 1
Probability of selecting a person who will vote for Candidate 1 or 2:
Total number of voters = 2500
Number of voters who support Candidate 1 = 250
Number of voters who support Candidate 2 = 1250
P(Candidate 1 or 2) = P(Candidate 1) + P(Candidate 2) - P(Candidate 1 and 2)
P(Candidate 1 or 2) = 250/2500 + 1250/2500 - 0
P(Candidate 1 or 2) = 1500/2500
P(Candidate 1 or 2) = 0.6
If 1,000 more voters are surveyed, the number of voters who will likely prefer Candidate 3 or 4 can be calculated as follows:
Number of voters who support Candidate 3 = 450
Number of voters who support Candidate 4 = 550
P(Candidate 3 or 4) = P(Candidate 3) + P(Candidate 4) - P(Candidate 3 and 4)
P(Candidate 3 or 4) = 450/3500 + 550/3500 - 0
P(Candidate 3 or 4) = 1000/3500
P(Candidate 3 or 4) ≈ 0.2857
Question 2
Probability of selecting an apple or an orange:
Total number of fruits = 20 + 4 + 12 = 36
Number of apples = 20
Number of oranges = 12
P(apple or orange) = P(apple) + P(orange)
P(apple or orange) = 20/36 + 12/36
P(apple or orange) = 32/36
P(apple or orange) = 8/9
Question 3
Probability of selecting an employee who eats breakfast or lunch:
Total number of employees = 80
Number of employees who eat breakfast = 20
Number of employees who eat lunch = 50
Number of employees who eat both breakfast and lunch = 15
P(breakfast or lunch) = P(breakfast) + P(lunch) - P(breakfast and lunch)
P(breakfast or lunch) = 20/80 + 50/80 - 15/80
P(breakfast or lunch) = 55/80
P(breakfast or lunch) = 0.6875
Question 4
Results of 150 trials of spinning letters C and E:
| C and E | Frequency |
|----------|----------|
| Yes | 21 |
| No | 129 |
Probability of spinning letters C and E ≈ 21/150 ≈ 0.14
Theoretical probability of spinning letters C and E:
P(C) = 1/5
P(E) = 1/5
P(C and E) = P(C) * P(E) = 1/5 * 1/5 = 1/25 = 0.04
The experimental probability in part (c) is higher than the theoretical probability in part (d).
Question 5
Simulation for client choosing model B with a car garage:
| Model B with car garage | Frequency |
|---------------------------|----------|
| Yes | 25 |
| No | 125 |
Probability of a client choosing model B with a car garage ≈ 25/150 ≈ 0.1667