University:
Minnesota State University Moorhead
Course:
MATH-335 | Intermediate Probability and Statistics I
Academic year:

2020
Views:

485

Pages:

2
Author:

gildnar99xu

Quiz 5.2A Statistics Name: 1. Suppose you choose a random U.S. resident over the age of 25. The table below is a probability model for the education level the selected person has attained, based on data from the American Community Survey from 2006-2008. Education level attained Probability No high school diploma 0.20 High School diploma or GED 0.22 Some college 0.29 Bachelor's degree 0.19 Graduate or professional degree 20.1 (a) What is the probability that a randomly selected person has a graduate or professional degree? (That is, fill in the space marked with a "?") Show your work. P(NONE) 1 PCAP) + Pcsone) + P(Bath) + P(gratisk) = 1 0.2 +0.22 +0.29 0.19 0.9 + x = 1 x = 0.1 + x = 1 (b) What is the probability that a randomly-selected person has at least a high school diploma? Show your work. Plot kost HS) = P(HS) + C(g) PCBach) 1PC Grachat = 0.22 + 0.29 * 4 * 0.19 + 1 6.8 OR Plot least HS) = 1-PL no high school) 2. There are 35 students in Ms. Ortiz's Precalculus class. One day, 24 students turned in their homework and 14 turned in test corrections. Eight of these students turned in both homework and test corrections. Suppose we randomly select a student from the class. (a) Fill in the Venn diagram below so that it describes the chance process involved here. Let H = event "turned in homework" and C = the event "turned in corrections." 5 + 6 = X Some muy, rave tema ndung in 요 35 35 n = 35 35 (b) What is the probability that a randomly-chosen student turned in neither homework nor corrections? Justify you answer with appropriate calculations. P(neithes)= 1 - [P(H) + P(c) + P(bo + w)] = 1 - [16/35 + 8/55 + 6/35] = 1/7 -[] 5/35 3. Below is a two-way table that describes responses of 120 subjects to a survey in which they were asked, "Do you exercise for at least 30 minutes four or more times per week?" and "What kind of vehicle do you drive?" Exercise? Yes No Total Car type SUV 15 20 24. 45 39 Sedan 25 Truck 12 24 36 Total 52- 68 120 Suppose one person from this sample is randomly selected. (a) List two mutually exclusive events for this chance process. Sedan and SUV others (b) What is the probability that the person selected drives an SUV? P(Sui) = 39/120 = 13/40 (c) What is the probability that the person selected drives either a sedan or a truck? P(Sedan or truck) = P(Sedan) + PCivicck)= mutually exclusive - 15/120 + 34/120 * 81/120 = 27/40 (d) What is the probability that the person selected drives a truck of exercises four or more times per week? PC truck on yeu) P(truck) + not mutually exclusive. Plyes)- Petruck yes) = 36/120 + 52/120 - 12/120 = 76/120 = 19/30