Stats Test Review

Which of the following must be true in order to use a sample to approximate a normal distribution?

The average SAT score in the state of North Carolina is 1090, with a standard devaiation of 120 points. What is the probability that I score an 810 on my SAT? (If the z-score is a repeating decimal, round it to the nearest hundredth before calculating the probability)

The average SAT score in the state of North Carolina is 1090, with a standard devaiation of 120 points. What is the probability that I score between an 1120 and a 1300 on my SAT? (If the z-score is a repeating decimal, round it to the nearest hundredth before calculating the probability)

Find the probability between the two z scores z = 0.4 and z = 2.63

• 2.23

• 0.3403

• -0.3403

• -0.34

There are 80 people in the final math tournament, how would I express the number of ways to arrange the top 10 finishers using factorials?

A florist has 7 flower arrangements. If they need to pick the best 2 to submit to a contest, how many ways can they pick those 2?

You are creating a custom guitar. There are 14 styles to choose from. Colors are red, blue, pink, purple, green, and white. Neck sizes range from 30-36 inches and increase by increments of 1/2 an inch (think about how many options that creates). How many different ways can I customize a guitar?

• 1008

• 14!

• impossible to determine

• 1092

The population mean price of gasoline in Texas was 2.99 per gallon on a given week. A random sample of 45 gas stations is drawn from this population. What is the z-score if the mean price of the sample was between less than 2.45?