Quiz after Unit 5 Exam

  1. Adult men have weights that are normally distributed with a mean of 190 lbs and a standard deviation of 20 lbs. Men are considered to be overweight if they weigh more than 240 lbs. What percent of all men are considered overweight?

(A)0.0062

(B)0.1108

(C)0.3466

(D)0.0001

(E)0.2051

  1. Referring to the previous problem, if we take a sample of 5 men, what is the probability that the sample is overweight?

(A)0.0062

(B)3.859 x 10-36

(C)1.137 x 10-8

(D)0.1108

(E)0.2365

  1. P(A) = 0.25 and P(B) = 0.31 and P(A and B) = 0.0775. What can be said about the relationship between events A and B

(A)They are disjoint and independent

(B)They are disjoint but not independent

(C)They are not disjoint, but they ARE independent

(D)They are neither disjoint or independent

(E)Cannot be determined from the information given

  1. We want to analyze the relationship between the number of hours spent studying (X) and the score students get on an exam (Y) using an LSRL. We take a sample of students and find the average # of hours spent studying is 1.8 with a standard deviation of 0.3 hours. We also find that the average score on the exam is 78 points with a standard deviation of 9 points. The correlation between the two variables is 0.79. What is the LSRL equation?

(A)Y = 78 +0.79X

(B)Y = 0.0263 – 0.2514X

(C)Y = 23.7 + 35.34X

(D)Y = -0.2514 + 0.0263X

(E)Y = 35.34 + 23.7X

  1. An experiment compares two brands of automobile tires. Each of a number of cars is equipped with one tire of each brand on a rear wheel (the order is randomized from car to car) and tread wear is measured periodically. This is called a

(A)simple random sample.

(B)stratified random sample.

(C)completely randomized design.

(D)matched pairs design.

(E)double-blind design.

  1. A researcher identified 100 men over 40 years old who were not exercising regularly and another 100 men over 40 years old with similar medical histories who were exercising regularly. She followed all the men for several years to see if there was any difference between the two groups in the rate of heart attacks. This is an example of

(A)Survey

(B)Prospective Study

(C)Retrospective Study

(D)Matched pairs design

(E)Block design

  1. We want to test the effectiveness of fish oil on heart health. We have 600 men available for the experiment. 400 of the men do not exercise regularly and 200 do exercise regularly. Men will be randomly assigned to take a 200 mg fish oil pill, a 100mg fish oil pill, or a placebo. Also, each group will be assigned either a high protein or high carb diet. This experiment

(A)is completely randomized

(B)has three factors (exercising, pill, diet)

(C)has two factors (exercise and pill) blocked by diet

(D)has two factors (pill and diet) blocked by exercise

(E)has one factor (pill) blocked by exercise and diet

  1. In a certain electronics store, 60% of TVs are LCDs. The probability of a TV being an LCD and a Samsung is 35%. What is the probability that a TV is a Samsung given that it is an LCD?

(A)1.714

(B)0.583

(C)0.21

(D)0.35

(E)0.60

  1. I have a distribution that is right skewed. Which of the following is most likely the relationship between the measures of center?

(A)Mean < median < mode

(B)Median < mode < mean

(C)Mode < mean < median

(D)Mode < median < mean

(E)Mean < mode < median

  1. The test scores for Block 3 AP Stat had a mean of 80 and a standard deviation of 10. The test scores for Block 2 AP Stat had a mean of 75 and a standard deviation of 9. What is the combined mean and standard deviation of the two classes? In other words, what is the mean and the standard deviation of Block 2 + Block 3?

(A)Mean = 5, standard deviation = 1

(B)Mean = 5, standard deviation = 13.45

(C)Mean = 155, standard deviation = 1

(D)Mean = 155, standard deviation = 13.45

(E)Mean = 77.5, standard deviation = 9.5