Math 415 Summer 2018 Midterm Exam Name MULTIPLE CHOICE. Choose the one alternati
ID: 3067914 • Letter: M
Question
Math 415 Summer 2018 Midterm Exam Name MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers question. 1) Gina and Stewart are surf-fishing on the Atlantic coast, where both bluefish and 1) pompano are common catches. The mean length of a bluefish is 261 millimeters with a standard deviation of 63 mm. For pompano, the mean is 154 mm with a standard deviation of 40 mm. Stewart caught a bluefish that was 320 mm long, and Gina caught a pompano that was 189 mm long. Who caught the longer fish, relative to fish of the same species? A) Neither. Relative to its respective species, the fish are the same length. B) Gina C) Stewart 2) Disease Present Disease Not Present Test Positive 10 Test Negative 18 Calculate the Prevalence using the information from the table above A) 46% B) 98% C) 43% D) 38% 3) The following frequency distribution presents the frequency of passenger vehicles that pass through a certain intersection from 8:00 AM to 9:00 AM on a particular day Vehicle Type Frequency Motorcycle Sedan SUV Truck 14 76 85 What is the relative frequency of the Motorcyle category? B) 14 A) 0.064 C) 0.165 D) 14%Explanation / Answer
1) here as z score =(X-mean)/std deviation
therefore Stewart Bluefish z score =(320-261)/63=0.94
and Gina pompano z score =(189-154)/40=0.88
as z score for Stewart Bluefish is higher therefore option C is correct
2)
prevalence =total who have disease/total sample =(16/42)*100=38.0% ; optin D
3)
relative frequency of motorcycle =(14/(14+76+85+44))=0.064 ; option A