Taking a Chance!
How do we name the Problem of the Day?
What is the District POD?
Trevor runs a basketball camp. A group of randomly selected camp participants were asked to give their shirt sizes. 30 camp participants need a large size from a 60 participatin random sample. There are 308 camp participants this year. Write the sample ratio.
30/60
A survey of 1,015 U.S.adults found that 32% have had to put off medical care for themselves or their family in the past year due to cost.
Population: U.S. adults
Sample: 1,015 U.S. adults surveryed
The entire group being studied.
What is the population?
is this biased?
caesar wanted to know how many people like pepperoni pizza so he asked every onethat worked in little caesars
yes this is biased
The head of a student council at a school with 200 total students conducts a survey among 30 randomly selected students. In the survey, he asks each student’s first choice for an after-school activity. Basketball is the first choice for 6 of the students. Write the sample ratio
6/30
Juanita surveys 50 adults at a local swimming pool during the summer to determine the favorite month of adults in her city.
Population: adults in her city
Sample: 50 adults at the local swimming pool
Parts of the group being studied.
What is a sample?
A large school district wants to find out which electives its students would prefer.
Which procedure would be most likely to obtain a statistically unbiased sample?
A. Survey a random sample of students from a list of all students in the district.
B. Invite all students to indicate their choices by e-mail.
C. Place suggestion boxes at random schools in the cafeterias and media centers.
D. Assemble a group of students, one student per school and record the preferences of these students.
A. Survey a random sample of students from a list of all students in the district.
Sally works at a frozen yogurt shop that has about 2,500 customers per week and wants to know how many people like vanilla frozen yogurt. She asks the question to 40 randomly selected customers. She repeats this process two more times. Sally finds that 14 people said they like vanilla frozen yogurt in the first sample, 18 in the second, and 12 in the third.
14/40
18/40
12/40
A survey of 1,353 American households found that 18% of the households own a computer
Population = American households
Sample = 1,353 American household
A sample in which each individual or object in the entire population has an equal chance of being selected.
What is a random sample?
Each of the samples below is randomly selected from a company with 320 employees. Choose which samples are representative samples for the company. Select all that apply.
A. 25 employees on the company e-mail list
B. 25 employees with 10 years of service or more
C. 25 employees as they begin their shifts at 3:00pm
D. 25 employees at a company-wide assembly
E. 25 employees from the human resource department
A. 25 employees on the company e-mail list
D. 25 employees at a company-wide assembly
The head of a student council at a school with 200 total students conducts a survey among 30 randomly selected students. In the survey, he asks each student’s first choice for an after-school activity. Basketball is the first choice for 6 of the students. Based on these survey results, how many students at the school would be expected to select basketball as an after-school activity? (Write the answer as a population ratio)
40/200
Every hundredth resident of voting age listed on the county census was surveyed about building a library.
Population: residents of voting age in the county
Sample: every hundreth resident
A sample that has the same characteristics of the population.
What is the representative sample?
Sam is a school leader. She wants to decide whether makeup should be allowed in school or not? She collected random samples of 100 females regarding make up preference. Make at least two inferences based on the results.
Mascara Lipstick Eyeliner Total
Sample #1 46 26 28 100
Sample #2 60 17 23 100
anwers may vary
Trevor runs a basketball camp. A group of randomly selected camp participants were asked to give their shirt sizes. 30 camp participants need a large size from a 60 participatin random sample. There are 308 camp participants this year. Write the population ratio.
154/308
A reseacher test to see if the mean annual salary of family practictioners in Los Angeles is moe than #178.258. A survey of 55 randomly chosen family practitioners in Los Angeles found that their mean annual salary was $192,340.
Population: family practictioners in Los Angeles
Sample: 55 randomly family practitioners in Los Angeles
What is Data?