9th grade Estimate a population from a sample survey, with the margin of error given worksheet

Estimate a population from a sample survey, with the margin of error given

Grade 9 Math Worksheet

Circle the best answer, or write your answer on the line.

1. 1.

   A random sample of 200 of the 1200 students at Esme's school found 30% bike to school, margin of error 6 percentage points. At the highest estimate, how many of the 1200 bike?
2. 2.

   A random sample of 160 of the 800 students at Jun's school found 45% carry a water bottle, margin of error 8 percentage points. At the lowest estimate, how many of the 800 carry one?
3. 3.

   A random sample of 250 of the 2000 students at Kira's school found 64% eat breakfast at school, margin of error 6 percentage points. At the highest estimate, how many of the 2000 eat there?
4. 4.

   A random sample of 100 of the 600 students at Milo's school averaged 3.5 books read this summer, margin of error 0.5. What is the lowest estimate of the total for all 600?
5. 5.

   A random sample of 90 of the 450 students at Noah's school averaged 1.6 hours of homework a night, margin of error 0.2. What is the highest estimate of the total for all 450?
6. 6.

   A random sample of 150 of the 750 students at Ren's school averaged 22 minutes walking a day, margin of error 3. What is the highest estimate of the total for all 750?
7. 7.

   A random sample of 150 students found a mean of 7.6 hours of sleep, margin of error 0.4 hours. Tala says the value for all students is 7.9 hours. Is that believable?

   • Yes: 7.9 hours is inside the interval, 7.2 to 8 hours.
   • No: the survey found 7.6 hours, so the true value is 7.6 hours.
   • No: 7.9 hours is outside 7.2 to 7.6 hours.
8. 8.

   A random sample of 360 students found that 38% want a school garden, margin of error 5 percentage points. Zee says the value for all students is 34%. Is that believable?

   • Yes: 34% is inside the interval, 33% to 43%.
   • No: the survey found 38%, so the true value is 38%.
   • No: 34% is outside 38% to 43%.
9. 9.

   its ends are not labeled. A random sample of 200 students found a mean of 25 minutes of reading a day, margin of error 3 minutes. Ari says the value for all students is 30 minutes. Is that believable?

   • No: 30 minutes is outside the interval, 22 to 28 minutes.
   • No: the survey found 25 minutes, so the true value is 25 minutes.
   • Yes: 30 minutes is close to 25 minutes.
10. 10.

    A random sample of 500 students found that 70% bring a water bottle, margin of error 4 percentage points. Bo says the value for all students is 60%. Is that believable?

    • No: the survey found 70%, so the true value is 70%.
    • Yes: 60% is close to 70%.
    • No: 60% is outside the interval, 66% to 74%.