Bus201 case 1
Math 201-Basic Statistics Jonathan Sainz
Dr. K 7/11/13
Case Assignment #1
1) 1. In a poll, respondents were asked whether they had ever been in a car accident. 177 respondents indicated that they had been in a car accident and 107 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?
177 people who have been in a car accident
107 people who have not been in a car accident
284 people in sample size
177/284=.62 or 62% of people from sample size have been in a car accident.
2) The data set represents the income levels of the members of a country club. Find the probability that a randomly selected member earns at least $102,000 INCOME (Thousands of dollars) 108 128 82 138 85 108 88 76 158 208 79 98 148 85 128 118 88 168 73 118
11 incomes of at least $102,000
20 members in sample size
11/20=.55 or 55% of members of golf course have an income of $102,000 or greater.
3) In a certain class of students, there are 13 boys from Wilmette, 3 girls from Kenilworth, 11 girls from Wilmette, 6 boys from Glencoe, 5 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?
8 students from Kenilworth
44 students in sample size
8/44=.18 or 18% of students are from Kenilworth
4) Find the probability of correctly answering the first 2 questions on a multiple choice test if random guesses are made and each question has 4 possible answers.
Joint probability of answering the first 2 questions of multiple choice correctly
(1/4)(1/4)=1/16=.06 or 6% chance of answer the first 2 questions correctly, if randomly guessed with 4 possible answers.
5) Of 1906 people who came into a blood bank to give blood,
Dr. K 7/11/13
Case Assignment #1
1) 1. In a poll, respondents were asked whether they had ever been in a car accident. 177 respondents indicated that they had been in a car accident and 107 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?
177 people who have been in a car accident
107 people who have not been in a car accident
284 people in sample size
177/284=.62 or 62% of people from sample size have been in a car accident.
2) The data set represents the income levels of the members of a country club. Find the probability that a randomly selected member earns at least $102,000 INCOME (Thousands of dollars) 108 128 82 138 85 108 88 76 158 208 79 98 148 85 128 118 88 168 73 118
11 incomes of at least $102,000
20 members in sample size
11/20=.55 or 55% of members of golf course have an income of $102,000 or greater.
3) In a certain class of students, there are 13 boys from Wilmette, 3 girls from Kenilworth, 11 girls from Wilmette, 6 boys from Glencoe, 5 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?
8 students from Kenilworth
44 students in sample size
8/44=.18 or 18% of students are from Kenilworth
4) Find the probability of correctly answering the first 2 questions on a multiple choice test if random guesses are made and each question has 4 possible answers.
Joint probability of answering the first 2 questions of multiple choice correctly
(1/4)(1/4)=1/16=.06 or 6% chance of answer the first 2 questions correctly, if randomly guessed with 4 possible answers.
5) Of 1906 people who came into a blood bank to give blood,