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Mixed Probability Questions

Solve the following problems showing your work:

1. In a poll, respondents were asked whether they had ever been in a car accident. 157 respondents indicated that they had been in a car accident and 117 respondents said that they had not been in a car accident. If one of these respondents is randomly selected, what is the probability of getting someone who has been in a car accident?

2. In a certain class of students, there are 12 boys from Wilmette, 3 girls from Kenilworth, 9 girls from Wilmette, 6 boys from Glencoe, 2 boys from Kenilworth and 6 girls from Glencoe. If the teacher calls upon a student to answer a question, what is the probability that the student will be from Kenilworth?

3. Find the probability of correctly answering the first 2 questions on a multiple choice test if random guesses are made and each question has 5 possible answers.

4. Of 1936 people who came into a blood bank to give blood, 200 people had high blood pressure. Estimate the probability that the next person who comes in to give blood will have high blood pressure.

Solution Preview

1. P(accident)
= CountAccident / CountTotal
= 157 / (157 + 117) = 157 / 274 = 0.573 = 0.573 * 100% = 57.3%

2. P(Kenilworth)
= CountKenilworth / CountTotal
= (3 girls + 2 boys) / ...

Solution Summary

The solution provides answers to four probability questions and shows the steps of the calculations.