Question

191 Math 134-5, 9, 10, PS 16 Estimating a population Mean Total: 30 Points (14:16) Name: I CELLO S 1. Blood Alcohol Concentration: As per the National Highway Traffic Safety Administration, out of a random sample of 51 fatal crashes in 2013 in which the driver had a positive blood alcohol concentration (BAC), the mean BAC recorded was 0.167 gram per deciliter (g/dl) with a standard deviation of 0.010 g/dl. Determine a 90% confidence interval for the mean BAC in fatal crashes in which the driver had a positive BAC CE (141 = 2 points) df Write the formula for Error and show your calculations. (4 points) Label the curve (2 points) (4 points) Construct the Confidence interval for the population Mean - (2 points) Interpret: 2. Robert wishes to estimate the mean number of miles that his Buick Lacrosse can be driven on a full tank of gas. He fills up his car with regular unleaded gasoline from the same gas station 10 times and records the number of miles that he drives until his low-tank indicator light comes on. He obtains the data shown below. Miles 323.9 326,8 370.6 450.7 368.8 423.8 398.8 417.5 382.7 343.1 driven Construct a 98% confidence interval for the mean number of miles driven on a full tank of gas. Use the calculator function to find Mean and SD (2 points) ta -- (1+1 = 2 points) df- Write the formula for Error and show your calculations. (4 points) Label the curve (2 points) (2 points) Construct the Confidence interval for the population Mean u = (2 points) Interpret:

Answer 1

Answer 1:

C = 90%

x̄ = 0.167

s = 0.010

n = 51

df = n-1 = 51-1 = 50

tα/2 = t0.05 = 1.676 (Obtained using t value calculator)

Margin of Error = tα/2*s/sqrt(n) = 1.676*0.010/sqrt(51)

Margin of Error ME = 0.002

Confidence Interval = μ +/- ME

Confidence Interval = (0.167-0.002, 0.167+0.002)

Confidence Interval = (0.165, 0.169)

Interpretation: We are 90% confidence the the true population mean is between 0.165 and 0.169 g/dl

*** Dear Student, We can answer one question per post. Please post remaining questions separately***