Crash testing is a highly expensive procedure to evaluate the ability of an automobile to withstand a serious accident. a simple random sample of 13 small cars were subjected to a head-on collision at 40 miles per hour. of them 8 were “totaled,” meaning that the cost of repairs is greater than the value of the car. another sample of 17 large cars were subjected to the same test, and 5 of them were totaled. let px represent the population proportion of small cars that are totaled and let py represent the population proportion of large cars that are totaled. find a 95% confidence interval for the difference px – py . round the answers to four decimal places.

-0.0205 < p1 - p2 < 0.6631

Step-by-step explanation:

Here we need to use the formulas for a confidence interval using a difference of 2 given proportions.

Proportion 1 (small cars) = 8/13

Proportion 2 (large cars) = 5/17

A 95% confidence level has a z-score of 1.96 (the method of looking up z-scores doesn't change with using two proportions instead of 1)

See attached photo for formulas and solutions, and the construction of the confidence interval...

what is the question here

step-by-step explanation:

first, we define the variables:

x: number of years after 1950

f (x): amount of vinyl sold.

then, with the variables defined, we have:

68594 vinyl records were sold in 1958 > f (8) = 68594

91299 vinyl records were sold in 1961 > f (11) = 91299

38720 vinyl records were sold in 1952 > f (2) = 38720

161743 vinyl records were sold in 1967 > f (17) = 161743

read more on -

step-by-step explanation: