Use what you have learned about mutually inclusive and exclusive events.
Apply the formula for calculating the probability of events A or B.
There are four presidential candidates in a country. A street survey was conducted asking 2,500 registered voters which candidate they will vote for in the coming election. The table summarizes the results of the survey.
Presidential Candidates Number of Supporters
Candidate 1 250
Candidate 2 1,250
Candidate 3 450
Candidate 4 550
Part 1: What is the probability of randomly selecting a person who will vote for Candidate 1 or 2
(2 points)
Responses
2502500
250 over 2500
15002500
1500 over 2500
10002500
1000 over 2500
12502500
1250 over 2500
Question 2
Part 2: If 1,000 more voters are surveyed, how many of them will likely prefer Candidate 3 or 4? Show your work and explain your answer.(2 points)
Part 1:
The probability of randomly selecting a person who will vote for Candidate 1 or 2 is calculated by adding the number of supporters for Candidate 1 and Candidate 2, and then dividing by the total number of voters surveyed.
Probability = (250 + 1250) / 2500
Probability = 1500 / 2500
Probability = 0.6
Therefore, the probability of randomly selecting a person who will vote for Candidate 1 or 2 is 0.6 or 60%.
Part 2:
If 1,000 more voters are surveyed, the number of supporters for Candidate 3 or 4 can be calculated by adding the number of supporters for Candidate 3 and Candidate 4.
Total number of supporters for Candidate 3 and 4 = 450 + 550
Total number of supporters for Candidate 3 and 4 = 1000
Therefore, if 1,000 more voters are surveyed, it is likely that 1,000 of them will prefer Candidate 3 or 4.