Estimating a Population Mean or Proportion Using Sample Surveys

You sample 12 bugs and find the sample mean is 2.40 cm. You are told the standard deviation is 0.2 cm. Find a 95% Confidence Interval.

• 2.40

• σ

• 1.96

• Z

• .2

• n

• 12

• μ

The student council randomly selected 25 students in the school to ask them to choose their favorite chips. The results of the random sample survey are in the table.

Based on the survey, about how many total students should the student council expect to choose Takis as their favorite if there are 538 students in the school?

• about 172 students

• exactly 172.16 students

• exactly 172 students

• exactly 173 students

Estimate the population proportion from the dotplot.

Mathematical Equivalence

ON

Of the 50 fish John caught from the lake, 14 were trout.  The estimated population of the lake is 7,500.  About how many trout would you expect to be in the lake?

• 2,100 trout

• 2,000 trout

• 2,200 trout

• 2,300 trout

Tags

CCSS.6.RP.A.1

CCSS.6.RP.A.2

CCSS.6.RP.A.3

What was the margin of error?

1300 people were surveyed concerning their thoughts on the upcoming election. What was the margin of error?

The amount added and subtracted to the statistic.

• Margin of Error

• Confidence Interval

• Z Score

• Population

How do you reduce the margin of error?

• Increase Sample Size

• Decrease Sample Size

Complete the following statement about the change in size. If you increase the size of your sample, the Margin of Error will . . . .

• get bigger

• get smaller

• stay the same

Tags

CCSS.HSS.IC.B.4

The label on an Animal Crackers box claims that there are 25 crackers in each box. Is this a reasonable claim?

• No, because 25 is outside the range of values in the table. 

• No, because we collected 28 samples. 

• Yes, because all the samples had at least 25 crackers in them. 

• Yes, because 25 is within the range of values in the table.