Exam 3: Numbers in the Real World

Answer the question. -Suppose that of the total amount collected in taxes by the U.S. government, 25% of it comes from families with incomes greater than $200,000. If taxes are increased by 5% across the board, which of the following statements will be true?

Use the appropriate rounding rule to answer the question with the correct precision or correct number of significantdigits. -The average amount spent on food last year by the residents of your town was $3300 per person. The population of your town is 41,790. What was the total amount spent on food last year by the Residents of your town?

Answer the question. -Which of the statements below suggests an appropriate level of precision?

Answer the question. -Which of the statements below suggests an appropriate level of precision?

Answer the question. -In Slackville, the unemployment rate was 20% last year and this year it is 24%. Which of the following statements is correct?

Solve the problem. -The table below shows the number of people testing positive for a certain disease amongst those who do have the disease and amongst those who don't. Use the table to answer the question. Test positive Test negative Total Disease 112 12 124 No disease 1001 8875 9876 Total 1113 8887 10,000 What percentage of those that tested negative actually have the disease?

Round to the indicated place value. -Round to the nearest ten: 62.3

Use scientific notation to solve the problem. -The national debt of a small country is $6,390,000,000 and the population is 2,256,000. What is the amount of debt per person?

Answer the question. -Suppose you are constructing a scale model solar system using a scale ratio of 1 to 200 billion. In your scale model what will be the distance from Saturn to the Sun (in meters)? The distance from Saturn to the Sun is 1427 million km.

Use scientific notation to perform the following operations. Leave your answer in scientific notation. - $\left( 2 \times 10 ^ { 7 } \right) \times \left( 6 \times 10 ^ { - 4 } \right)$

Restate the fact as indicated. -The national debt was about $6.9 trillion at the end of 2003. Express this quantity as the number of dollars per person. Assume a U.S. population of 280 million.

Round to the indicated place value. -Round to the nearest tenth: 1.42

Carry out the indicated operation and give your answer with the specified number of significant digits. - $984 \div 0.00869 ; 3$ significant digits

Solve the problem. -The table below shows the result of a polygraph test conducted on 2000 college students. Students were asked whether they had ever cheated on a test. All of them denied having cheated. Use the Table to answer the question. Test finds student lying Test finds student truthful Total Has cheated 84 13 97 Has not cheated 198 1705 1903 Total 282 1718 2000 What percentage of those that were lying were found to be truthful?

Round to the indicated place value. -Round to the nearest thousandth: 3.83366

Write as a percent. - $27.317$

Find the absolute and relative errors. -It took you one hour and 8 minutes to drive home, you estimated the time to be one hour and 23 minutes.

Answer the question. -Suppose that a test for a disease correctly gives positive results for 95% of those having the disease and correctly gives negative results for 92% of those who don't have the disease. Suppose also that The incidence of the disease is 1%. If a person tests positive for the disease, what can you say about Their chance of having the disease?

Determine ratio of A to B. Round as indicated. - $A = 260$ and $B = 360$ (Do not round.)

Give an appropriate response. -The tables below show the results of a study examining the incidence of breast cancer among women who exercise regularly and those who do not. The 425 women in the study were split into two age groups, those under 40 and those 40 or older. For each age group, determine the percentage of women having breast cancer among those exercise regularly and among those who do not exercise regularly. If the two age groups are combined, what percentage have breast cancer among those who exercise regularly and among those who do not exercise regularly? Explain the apparent inconsistency in these results, and how the design of the study brought about the inconsistency.