Statistics Final Exam Review

Participants rated two candies on a 0-10 scale. Perform a significance test to determine if the mean rating of Candy A is different than the mean rating of Candy B.

The table shown gives the probability that a customer will order a specific restaurant item. What is the probability that a customer will NOT order Pasta?

If you roll a standard six-sided die nine times what is the probability that you will roll the number 5 at least once? Round your answer to the nearest percent.

The table shown gives the probability that a customer will order a specific restaurant item. What is the probability that a customer will order a Vegan Entrée?

You conduct an SRS of 15 online and 18 seated students. The sample average for online is 86 with s=2; the sample average for seated is 90 and s=8.Use a significance test to decide if online students have lower grades? (α=5%).

From a bag containing a yellow, a red, an orange, a pink and a green ball, two balls are selected one after the other with replacement. Draw a tree diagram and list the sample space.

Suppose you draw ONE card from a standard deck of cards. What is the probability of drawing an ace OR a red card? Give your answer as a fraction in lowest terms.

Of a sample of 39,888 college applicants the average age was 19. The population standard deviation σ is 3 years. Find the 90% confidence interval of the true mean age of the students that applied to college. Round to the nearest thousandth.

The distribution of the length of time, that phone batteries hold a charge, is right-skewed with σ = 7 hours. The MyPhone Company desires a 95% confidence interval with a margin of error of approximately 1 hour. What sample size is needed?

The distribution of the amount of money that students spend on coffee per month is right skewed with μ = $10 and σ = $125. In a SRS of 30 students, what is the probability that these students will spend on average, less than $55 on coffee?

Wiki.com claims that teens average 6.5 hrs of sleep/night. You think that teens sleep longer than this and conduct a SRS of 100 teens, x ̅= 6.75 hrs and s = 1.5 hrs. Use a significance test to decide if Wiki.com claim is false (α=1%).

If you roll a standard die once, what is the probability of rolling an even number less than 6? Give your answer as a fraction in lowest terms.

The distribution of the length of time, that phone batteries hold a charge, is right-skewed with σ = 7 hours. The MyPhone Company desires a 95% confidence interval with a margin of error of approximately 1 hour. What sample size is needed?

The average annual rainfall, taken at 25 different Sonoran Desert locations is found to be 9.25” with s = 2.5”. Find the 95% confidence interval for the true average Sonoran Desert annual rainfall. Round to the nearest thousandth.

Suppose you draw two cards, one after another, with replacement from a standard deck of cards. What is the probability of drawing a black card AND a jack? Give your answer as a fraction in lowest terms.

Each time you play a certain game it is possible to lose $5, break even, or win $40. The probability for each outcome, X, is shown in the table. Calculate μx, the expected value for this game.  Round to the hundredths place.

Each time you play a certain game it is possible to lose $5, break even, or win $40. The probability for each outcome, X, is shown in the table. Calculate σx ,the standard deviation of X. Round to the hundredths place.

ShakeShack claims their shakes have 625 mL. In a SRS of 30 shakes you find an average of 619 mL. The shakes have σ = 5 mL. Use a significance test to determine if the company is underfilling their shakes (α=5%).

Final exam scores are normally distributed with μ = 75 points and σ = 15 points. What is the probability that a randomly selected student will score between 93 and 100 points? Round to the nearest percent.