1.Determine whether the following statement is true or false.

p-values are used to determine statistical significance.

True

False

2.In a drug trial, patients showed improvement with ap-value of0.04. Explain the meaning of thep-value in this trial.

There is only a% probability that the outcome would have occurred by chance alone if the drug had no effect.

Would such a result normally be considered to be statistically significant?

Yes, such a result would normally be considered to be statistically significant.

No, such a result would not normally be considered to be statistically significant.

3.Suppose we want to test the idea that unregulated diets for children lead to serious health problems. Comment on the ethics of the following experimental design. We select two groups of small children. We let one group eat whatever they want whenever they want it. The second group eats what nutritionists and physicians tell us is a healthy diet. At the end of a few years, we analyze the health of each group.

This survey should not be continued as we are willingly allowing children to harm themselves.

This survey will help to study the difference between unregulated and regulated diets of children.

Children will learn to eat a regulated diet.

A better ethical design would be to use the parents as the subjects.

4.A certain drug company announced that the results of a clinical trial for a new drug in patients with sunburn showed statistically significant improvement(p-value = 0.04).

The president of the company asserted that this shows that 96% of the subjects in the trial were helped by the drug. Discuss the validity of the president's comment.

The drug has 100% efficacy.

The number of subjects that participated in the clinical trial is needed in order to make any conclusions about the president's statement.

The drug has a greater effect than would be expected by chance.

96% of subjects were helped by the drug.

5.For each pair of variables, determine whether they are positively correlated, negatively correlated, or uncorrelated.

(a) Brightness of an oncoming car's headlights and your distance form the oncoming car

positively correlated

negatively correlated

uncorrelated

(b) The number of home runs hit by Barry Bonds in a year and my water bill for that year

positively correlated

negatively correlated

uncorrelated

(c) Damage in a city at the epicenter of an earthquake and the Richter scale reading of the earthquake

positively correlated

negatively correlated

uncorrelated

(d) A golfer's tournament ranking and her score

positively correlated

negatively correlated

uncorrelated

6.Suppose a certain medical study shows that over 90% of patients with mild to moderate flu recover within 10 to 12 days if they are exposed to fresh, clean air. What can we conclude from this information about the relationship between breathing clean air and curing the flu? Explain the reasons for your answer.

The relationship between breathing clean air and curing flu does not imply moderation.

The relationship between breathing clean air and curing flu does not imply correlation.

The relationship between breathing clean air and curing flu does not imply probability.

The relationship between breathing clean air and curing flu does not imply causation

7.Find the area of a right triangle whose legs have lengths12and15.

units²

^8.Find the length of the hypotenuse of a right triangle whose legs have lengths6and10. (Round your answer to one decimal place.)

units

9.The hypotenuse of a right triangle has length13, and a leg has length4. Find the area of the triangle. (Round your answer to two decimal places.)

units²

10.The following exercise uses Heron's formula.

Find the area of a triangle with sides8,8, and10. (Round your answer to one decimal place.)

units²