Estimating a population quantity from a sample
Estimating a population quantity from a sample.
- Sample proportion = number with the property ÷ sample size.
- Estimated population number = sample proportion × population size.
- State that it is an estimate and relies on a representative sample.
Example 1
A representative sample of 40 students contains 7 that walk to school. There are 400 students in the population. Estimate how many walk to school.
This is an estimate, not a guaranteed total. It relies on the sample representing the population.
Example 2
A representative sample of 50 households contains 8 that own a bicycle. There are 500 households in the population. Estimate how many own a bicycle.
This is an estimate, not a guaranteed total. It relies on the sample representing the population.
Your turn
A representative sample of 60 books contains 9 that need repair. There are 600 books in the population. Estimate how many need repair.
Check answer
This is an estimate, not a guaranteed total. It relies on the sample representing the population.
A representative sample of 70 students contains 10 that walk to school. There are 700 students in the population. Estimate how many walk to school.
Check answer
This is an estimate, not a guaranteed total. It relies on the sample representing the population.
A representative sample of 80 households contains 11 that own a bicycle. There are 800 households in the population. Estimate how many own a bicycle.
Check answer
This is an estimate, not a guaranteed total. It relies on the sample representing the population.
A representative sample of 40 books contains 12 that need repair. There are 440 books in the population. Estimate how many need repair.
Check answer
This is an estimate, not a guaranteed total. It relies on the sample representing the population.
A representative sample of 50 students contains 13 that walk to school. There are 550 students in the population. Estimate how many walk to school.
Check answer
This is an estimate, not a guaranteed total. It relies on the sample representing the population.
A representative sample of 60 books contains 9 that need repair. There are 600 books in the population. Estimate how many need repair.
AnswerThis is an estimate, not a guaranteed total. It relies on the sample representing the population.
A representative sample of 70 students contains 10 that walk to school. There are 700 students in the population. Estimate how many walk to school.
AnswerThis is an estimate, not a guaranteed total. It relies on the sample representing the population.
A representative sample of 80 households contains 11 that own a bicycle. There are 800 households in the population. Estimate how many own a bicycle.
AnswerThis is an estimate, not a guaranteed total. It relies on the sample representing the population.
A representative sample of 40 books contains 12 that need repair. There are 440 books in the population. Estimate how many need repair.
AnswerThis is an estimate, not a guaranteed total. It relies on the sample representing the population.
A representative sample of 50 students contains 13 that walk to school. There are 550 students in the population. Estimate how many walk to school.
AnswerThis is an estimate, not a guaranteed total. It relies on the sample representing the population.