Portage Learning MATH 110 Introduction to Statistics Final Exam 2022 -Complete Solutions (Graded A)

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Final Exam Question 1 Not yet graded / 10 pts You may find the following files helpful throughout the exam: The following pie chart shows the percentages of total items sold in a month in a certai... n fast food restaurant. A total of 4700 fast food items were sold during the month. a.) How many were fish? b.) How many were french fries? Your Answer: a. fish 4700(0.28)=1316 b. French fries 4700(0.4)=1880 a.) Fish : 4700(.28) = 1316 b.) French Fries: 4700(.40) = 1880 Question 2 Consider the following data: 430 389 414 401 466 421 399 387 450 407 392 410 440 417 471 Find the 40th percentile of this data. There are a total of fifteen numbers, so n= 15. In order to find the percentiles, we must put the numbers in ascending order: 387 389 392 399 401 407 410 414 417 421 430 440 450 466 471 For the 40th percentile: Therefore, the 40th percentile index for this data set is the 6th observation. In the list above, the 6th observation is 407. Question 3 In a tri-state conference, 60% attendees are from California, 25% from Oregon, and 15% from Washington. As it turns out 6 % of the attendees from California, 17% of the attendees from Oregon, and 12% of the attendees from Washington came to the conference by train. If an attendee is selected at random and found to have arrived by train, what is the probability that the person is from Washington? P(Train│C)=.06.. P(Train│O)=.17.. P(Train│W)=.12.. P(C)=.60,P(O)=.25,P(W)=.15. We want to find P(W│Train), so use: Question 4 Find each of the following probabilities: a. Find P(Z ≤ -0.87) . b. Find P(Z ≥ .93) . c. Find P(-.59 ≤ Z ≤ -.36). a. P(Z ≤ -0.87)= .19215. b. P(Z ≥ .93)=1- .82381= .17619. c. P(-.59 ≤ Z ≤ -.36)= .35942- .27760= .08182. Question 5 Suppose that you are attempting to estimate the annual income of 1700 families. In order to use the infinite standard deviation formula, what sample size, n, should you use? In order to use infinite standard deviation formula, we should have: n≤0.05(1700) n≤85 So, the sample size should be less than 85. Question 6 A shipment of 450 new blood pressure monitors have arrived. Tests are done on 75 of the new monitors and it is found that 15 of the 75 give incorrect blood pressure readings. Find the 80% confidence interval for the proportion of all the monitors that give incorrect readings. Answer the following questions: 1. Multiple choice: Which equation would you use to solve this problem? A. B. C. D. E. 2. List the values you would insert into that equation. 3. State the final answer to the problem We have a finite population, so we will use Case 2: E. The proportion of the sample that are defective is 15/75 = .2 so we set P=.2. As we mentioned previously, we estimate p by P. So, p=.2. A total of 75 monitors were tested, so n=75. Based on a confidence limit of 80 %, we find in table 6.1 that z=1.28. The total number of monitors is 450, so set N=450. Now, we can substitute all of these values into our equation: .2± .054 So the proportion of the total that are defective is between .146 and .254. Question 7 It is recommended that pregnant women over eighteen years old get 85 milligrams of vitamin C each day. The standard deviation of the population is estimated to be 9 milligrams per day. A doctor is concerned that her pregnant patients are not getting enough vitamin C. So, she collects data on 40 of her patients and finds that the mean vitamin intake of these 40 patients is 83 milligrams per day. Based on a level of significance of α = .015, test the hypothesis. H0: μ=85 milligrams per day [Show More]

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