Which is better, a score of 92 on a test with a mean of 71 and a standard deviation of 15, or a score of 688 on a test with a mean of 493 and a standard deviation of 150? 

“38% of adults in the United States regularly visit a doctor”. This conclusion was reached by a college student after she had questioned 520 randomly selected members of her college. Why is there an error in her conclusion?

Select the correct sampling method for each of the samples described below. A large school district includes 15 high schools.  The district selects 10 teachers from each high school and asks their opinon about a new curriculum.   A retail chain has 1503 locations.  Human Resources randomly selects 25 stores and asks all the employees at each of these stores their opinion about a new company policy.   A bicycle manufacturing facility selects every 65th frame from the assembly line and inspects it to make sure it meets specifications.   All students in a class are assigned a number from 1 – 32.  Five students are randomly selected using a random number generator.

Use the given information to find the minimum sample size required to estimate an unknown population mean μ. Margin of error: $135 Confidence level: 95% σ = $500

Describe the complement of this event:  Of ten adults, at least one of them has high blood pressure.

The size of the last 12 graduating classes of a certain high school are given below. 227 239 215 219 221 233 229 233 235 228 245 231 Mean:  Median:  Standard Deviation:  Round each answer to the nearest tenth as needed.

A spinner has equal regions numbered 1 through 15.  What is the probability that the spinner will stop on an even number, or a multiple of 3?  Give your answer as a decimal, rounded to 4 places.

Assume that the weight loss for the first month of a diet program is normally distributed with a mean of 11 pounds and a standard deviation of 4 pounds.  Find the probability a randomly selected person loses between 10 and 14 pounds during the first month on the diet program.  Give an answer rounded to 4 decimal places.

Determine if each situation is an observational study or an experiment: The Community Intervention Trial for Smoking Cessation (COMMIT) asked whether a community-wide advertising campaign would reduce smoking. The researchers located 11 pairs of communities that were similar in location, size, economic status, and so on. One community in each pair participated in the advertising campaign and the other did not. A sample of fish is taken from a lake to measure the effect of pollution from a nearby factory on the fish.  The amount of toxin in the livers of the fish is measured and recorded.    What electrical changes occur in muscles as they get tired? Student subjects hold their arms above their shoulders as long as they can. Meanwhile, the electrical activity in their arm muscles is measured.  

How many ways can 6 people be chosen and arranged in a straight line if there are 8 people to choose from?