Unit 3 Review

A cereal box contains exactly 1 out of 4 available prizes. Emily wishes to collect all 4 prizes and wonders how many boxes of cereal she should expect to buy if all the prizes are equally distributed. She performs 100 simulations of the problem and records the results in the dot plot below. Based on the results of the simulations, how many boxes of cereal should she expect to buy in order to collect all 4 prizes?

• 4
• 8
• 12
• 24

A student is curious about the average age of a penny in circulation. The student collects pennies for a few months and places them in a jar. Once the jar is full, the student mixes up the pennies, randomly selects 10 of them, records the age of each penny selected, and finds the average age. Which of the following best describes the way the average age of a penny in circulation was determined?

• This is a sample survey.
• This is an observational study.
• This is an experiment that used a controlled group.
• This is an experiment that did not use randomization.

The management of a restaurant with locations all over the country has developed a new milkshake that is currently sold. Which of the following is the best way to preform a randomized experiment with the goal of determining if this new milkshake will sell better than the milkshake that is currently sold. 

• Randomly select 50 regions from all regions throughout the country, have the restaurants in those region stop selling the current milkshake, and start selling the new milkshake to see if the sales increase.
• Have all the company's restaurants throughout the country stop selling the current milkshake and stat selling the new milkshakes to see if sales increase. 
• Randomly select 40 restaurants, let each one decide if it wants to sell the new milkshake, and compare sales in those restaurants to sales in the restaurants that chose not to sell the new milkshakes.
• Having all the restaurants in the northern part of the country stop selling the current milkshakes and start selling the new milkshake to see if these resturants' sales are higher than the resturants in the southern part of the country that continues selling the current milkshake.

Tajee wants to survey his awesome fabulous math class and choose to stand at the door with Ms. LaRosa and ask every fourth student to take the survey (and they don't have a choice!). Which type of sampling style did Tajee use?

• Systematic Random Sample
• Stratified Random Sample
• Convenience  Sample
• Simple Random Sample

Mya wants to survey her great math class and decides to ask Ms. LaRosa to pull 6 names out of a hat from the name tags on the board. Which sampling style did she use?

• Systematic Random Sample
• Simple Random Sample
• Stratified Random Sample
• Convenience

**REVIEW**
Which is the equation of the circle?

• (x-2)²+(y-3)²=4
• (x+2)²+(y+3)²=4
• (x-2)²+(y-3)²=16
• (x+2)²+(y+3)²=16

Anthony wants to survey his peers at lunch, so he gives his survey to the first 50 people he sees at lunch that agree to take his survey. What type of sampling did Anthony choose?

• Systematic Random Sample
• Stratified Random Sample
• Simple Random Sample
• Convenience Sample

Which method would be the best way to conduct an experimental study to determine the effects of Vitamin C for preventing colds?

• Ask 100 people who consume vitamin C if they got a cold.
• Ask 100 people who had a cold last winter if they consumed vitamin C on a regular basis and record the number.
• Divide 100 volunteers into two groups; one group will consume vitamin C and the other group will not consume vitamin C. After a period of time, see how many people in each group developed a cold.
• Interview 100 people and classify them as either never consuming vitamin C, sometimes consuming vitamin C, or consuming vitamin C on a regular basis. Check for any cold symptoms in all the patients and analyze results.

**REVIEW**
A cylinder is completely filled with water. The radius of the cylinder is 5 inches and its height is 10 inches. The cylinder loses 1.2 cubic inches of water per minute through a small leak. If no water is added, which of the following is closest to the number of minutes it will take to completely empty the cylinder?

• 654 minutes
• 785 minutes
• 942 minutes
• 1308 minutes

Which characteristic in a statistical study is necessary in order for conclusions to be drawn regarding the whole population, based on the sample population?

• The sample must be randomly selected.
• The sample must not be randomly selected.
• The population size must meet a minimum number requirement, based on the sample size.
• The population size must meet a maximum number requirement, based on the sample size.