Statistics- Mid-term Review

Front

What type of sampling is occurring if every nth person is chosen to be surveyed?

Back

Systematic

Front

What is the probability that a person chosen takes the bus to school, given that they are a junior?

Back

0.353

Front

With a mean of 80 and a standard deviation of 5, what is the percentile ranking of a person with a score of 75?

Back

16%

Front

If P(A) = 0.8 and P(B)= 0.6, find the probability of A or B occurring if they are independent events?

Back

0.14

Front

What is the probability that a person chosen is a senior that walks OR a junior that drives a car?

Back

0.338

Front

Which type of sampling would take place if you divided a population into groups and then took a simple random sample from each?

Back

Stratified

Front

Describe the shape of the graph pictured.

Back

Skewed right, mean > median

Front

For a random sample of 100 students screen time in a day, the mean was 120 minutes with a standard deviation of 10 minutes. What amount of screen time would give the rank of a 84th%tile?

Back

130 minutes

Front

A linear regression line has the equation y = 15x + 25, where x is the number of hours and y is the total cost of a bike repair. What is the hourly rate of the repair shop?

Back

$15 per hour

Front

Find the z-score of an exam grade of 90 with a mean of 75 and a standard deviation of 8.

Back

1.875