Marin of Error Yay!

4010 people were surveyed concerning their thoughts on the upcoming election. What was the margin of error?

A recent survey found that out of 400 random American adults, 89% pay their bills on time. The margin of error in this survey was 2%. What is the interval of values in which the truth is likely found?

• 89% - 91%

• 87% - 89%

• 87% - 91%

• 388 - 402

A recent survey found that 77% of high schoolers use their phones more than 4 hours a day on average. The margin of error was 3%. What is the interval for which we could expect to find the truth of the population?

• 77% - 80%

• 74% - 77%

• 74% - 80%

• 50 million high schoolers - 120 million

What kind of sample technique is the following:

Survey 130 names chosen out of a hat.

• Convenience Sampling

• Simple Random Sampling

• Systematic Sampling

• Sample

A random sample of 40 bags of Doritos was obtained.

The mean weight was 15.5 oz with a standard deviation of 0.2 oz.

Find the margin of error of the sample.

A researcher stood at a school parking lot entrance to see if the color of a car is related to the driver not wearing a seatbelt.

• Observational Study

• Experiment

Four groups of randomly selected people are assigned a different diet. After six months, the blood pressures of each group are compared.

• Observational Study

• Experiment

Why is a sample of 1000 people better than a sample of 100 people?

• It reduces the margin of error.

• It decreases bias.

• Having more people is always better.

• More people means that our results are more accurate.

I have 100 apples in bag with a margin of error of 2%

What is my range

• 100 to 104

• 98 to 100

• 96 to 104

• 98 to 102

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