Tell whether the sample is likelyor unlikelyto be a representative
sample of the whole population. If unlikely, explain why.- Palo wants to find the favorite beach 8. To find the favorite hobbies of the
of the swim team members. He writes students at school, Joanna asks the
each member’s name on a craft stick members of the chess club.
and chooses 10 names randomly.
Tell which method of selecting a sample is used. Write random sampling,
convenience sampling, or responses to a survey.- Philip chooses one name from each 10. Rhianne distributes a questionnaire
page of the phone book. and tallies the results she gets back. - Mickey e-mails a list of questions to 12. Elena questions people as they are
everyone in school. He records the leaving the bookstore.
results from the people who reply.
Use Samples to Predict
You can use data from a sample to predict data for an entire population.
A lake is estimated to have a fish population of 1000. Ten out of 50 fish are trout.
Based on this sample, predict about how many fish in the lake are trout.
Set up an equation.Find equivalent fractions
to solve for n.Out of about 1000 fish in the lake, about 200 are trout.
n 200200
100010 20
50 20ntrout
1000 fish in all10 trout
sample 50 fish in all populationThink
50 20 1000Predict the number of yesresponses from the population.- population: 1000 voters 14. population: 500 students
sample: 250 voters sample: 20 students
yesresponses from sample: 175 yesresponses from sample: 8 - Dr. Phillips samples 30 students to find the average distance students
live from school. His results indicate an average distance of 2.2 mi. The
actual average distance students live from school is 1.9 mi. Dr. Phillips
used a random sample. Explain why the average distance from the
survey is different from the actual average distance. - What results would Dr. Phillips get if he randomly sampled another
30 students?
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