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More with the normal curves…. 6.3 Approximate Binomial Distribution & Test Hypotheses. about 68% of a data set lies in the range about 95% of a data set lies in the range almost all of a data set lies in the range. 34% of your data. 34% of your data. 13.5% of your data.

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More with the normal curves…

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More with the normal curves…

6.3 Approximate Binomial Distribution & Test Hypotheses

about 68% of a data set lies in the range

about 95% of a data set lies in the range

almost all of a data set lies in the range

Normal Distribution:

A bell-shaped, normal curve that is symmetric about the mean; total area under the curve is 1

Bubye Penny?

23% of adults in the U.S. favor abolishing the penny and making the nickel the lowest denomination coin.

You are conducting a random survey of 500 adults. What is the probability that you will find at most 106 adults who favor abolishing the penny?

23% of adults in the U.S. favor abolishing the penny and making the nickel the lowest denomination coin.

You are conducting a random survey of 500 adults. What is the probability that you will find at most 106 adults who favor abolishing the penny?

WHOA! Way too much work!

• 23% of adults in the U.S. favor abolishing the penny and making the nickel the lowest denomination coin.

• You are conducting a random survey of 500 adults. What is the probability that you will find at most 106 adults who favor abolishing the penny?

n = trials p = probability

Normal Distribution

You try:

• Hyperopia is a condition that affects approximately 25% of the adult population in the U.S. Consider a random sample of 280 U.S. adults.

a.) What is the probability that 63 or more people are farsighted?

b.) What is the probability that fewer than 84 people are farsighted?

c.) What is the probability that at most 65 people are farsighted?

Accel math 2 period 6

Rejection?

• If you test a claim (a hypothesis) by collecting your own data, and if the probability of the event occurring is less than 5% then you should reject the original claim.

Do you trust everything you read?

• A recent Harris Poll claimed that 44% of adults cut back on their spending in order to pay for increased gas prices.

• To test this, you surveyed (hypothetically) 60 adults and found 21 of them cut back on spending in order to pay for gas.

• Should you reject the Harris Poll’s findings?

You try…

• Rework the example if 18 people out of the 60 adults cut back on their spending.