MATH

Lesson 2.3

#1 Points possible: 5. Total attempts: 5

Are these two quantities necessarily equal?

· No, they may not be equal

· Yes, they are equivalent

#2 Points possible: 10. Total attempts: 5

For each quantity, what information would you need to compute these percentages?

For Quantity 1 (Q1):  (select all you would need)

· Total number of smokers in the population

· Total number of women in the population

· Total number of women smokers in the population

For Quantity 2 (Q2):  (select all you would need)

· Total number of smokers in the population

· Total number of women in the population

· Total number of women smokers in the population

 

Percents from Data

Suppose a study on smoking was conducted at Midland University. The following table indicates the results of the study.  Use this table for the next 3 questions.

	Men	Women
Smokers	4,572	5,362
Nonsmokers	10,284	12,736

#3 Points possible: 5. Total attempts: 5

What percentage of women smoke at Midland University (round to the nearest one percent)?

%

#4 Points possible: 5. Total attempts: 5

What percentage of smokers at Midland University are women (round to the nearest one percent)?

%

#5 Points possible: 5. Total attempts: 5

How many women would need to stop smoking for the percentage of women who smoke to drop below 20%?

 women

Suppose a study was conducted at Northwest College. The following table indicates the results of the study. Use this table for the next 3 questions.

	Men	Women
Smokers	1,256	536
Nonsmokers	1,028	1,053

#6 Points possible: 5. Total attempts: 5

What percentage of women smoke at Northwest College (round to the nearest one percent)?

%

#7 Points possible: 5. Total attempts: 5

What percentage of smokers at Northwest College are women (rounded to the nearest one percent)?

%

#8 Points possible: 5. Total attempts: 5

Just looking at the data, without making any calculations, which of the following statements is true?

· More than 70% of men smoke

· More than 50% of men smoke

· Less than 25% of men smoke

· Less than 50% of men smoke

#9 Points possible: 5. Total attempts: 5

Men smokers make up what percentage of the total student body (rounded to the nearest one percent)?

%

Percent Intuition

In 2006, the World Health Organization conducted a study about smoking in the United States and China. The organization reports that 3.7% of the adult women in China smoke tobacco products. In the United States, 19% of adult women smoke. Without using a calculator, answer the following questions.

#10 Points possible: 5. Total attempts: 5

Out of 100 adult women in China, about how many are smokers?  (Give a whole number of people)

 out of 100

#11 Points possible: 5. Total attempts: 5

Out of 1000 adult women in China, about how many are smokers?

 out of 1000

#12 Points possible: 5. Total attempts: 5

Out of 100 adult women in the United States, about how many are smokers?

 out of 100

#13 Points possible: 5. Total attempts: 5

Out of 1000 adult women in the United States, about how many are smokers?

 out of 1000

#14 Points possible: 5. Total attempts: 5

Are there more women smokers in China or the United States?

· More in China

· More in the United States

· Not enough information given to tell

#15 Points possible: 5. Total attempts: 5

Suppose you read that 590 out of 1,000 men in China smoke. Based on these data, what percentage of men in China smoke?

%

Different Representations

A teacher has collected data on the grades his students received in his two classes. The following tables show two different ways to represent the same data.

Table 1

	Grades
	A	B	C	D	F
Morning Class	12.5%	25.0%	37.5%	6.3%	18.8%
Afternoon Class	14.3%	20.0%	37.1%	8.6%	20.0%

 

Table 2

	Grades
	A	B	C	D	F
Morning Class	44.4%	53.3%	48.0%	40.0%	46.2%
Afternoon Class	55.6%	46.7%	52.0%	60.0%	53.8%

#16 Points possible: 10. Total attempts: 5

a) Which table could be used to answer the following question: “What percentage of the students who received an A are in the morning class?”

· Table 1

· Table 2

· Neither table

b) Which table could be used to answer the following question: “What percentage of the students in the morning class received an A?”

· Table 1

· Table 2

· Neither table

 

HW 2.3

#1 Points possible: 5. Total attempts: 5

Which of the following was one of the main mathematical ideas of the lesson?

· A percentage is calculated by dividing one number by another number.

· A percentage is a comparison of two numbers. To understand the meaning of a percentage, it is important to know what two quantities are being compared.

· The percentage of students who are parents is the same as the percentage of parents who are students.

· Smoking is a major health problem in the United States and China.

#2 Points possible: 25. Total attempts: 5

Data from the National Postsecondary Student Aid Study provides a statistical snapshot of the proportion of community college students who majored in different fields of study in 2003-04. A total of 25,000 community college students were included in the study. The table below displays the total number of community college students who majored in each of the following fields of study in 2003-04.

Field	Number of Students who Majored in Field	Percentage of Students who Majored in Field
Humanities	3,700	%
Social/Behavioral Sciences	1,250	%
Mathematics and Science	900	%
Computer/Information Science	1,525	%
Engineering	1,025	%
Education	2,025	%
Business/Management	4,600	%
Health	5,975	%
Vocational/Technical	1,225	%
Other Technical/Professional	2,775	%

a. Complete the table by filling in the percent of community college students who majored in each field of study. Round to the nearest one percent.

b. What was the most popular major in 2003–04? 

· Humanities

· Business/Management

· Education

· Health

c. Fill in the blanks to complete the following statements.  About  out of every 100 community college students in 2003–04 majored in the most popular field.  About  out of every 1,000 community college students in 2003–04 majored in the most popular field.

#3 Points possible: 5. Total attempts: 5

Select the answers that correctly complete the statement from the list below: A New York Times story reported that 10% of male high school dropouts are in jail or detention centers. According to this statistic, about ________ in every ________ male high school dropouts is (are) in jail or juvenile detention. There may be more than one correct answer.

· 1 in every 100

· 1 in every 10

· 10 in every 100

· 1 in every 10%

· 0.1 in every 100

#4 Points possible: 5. Total attempts: 5

From 2000 to 2006, a total of 19,076 teens ages 15–19 were killed in car crashes in the United States. The number of teen males who were killed was 12,479 and the number of teen females who were killed was 6,5972. A reporter used this information to write, “About 34%, or one out of every three girls will be killed in a car crash.” Which of the following statements is the best critique of this statement?

· The statement is correct because 6,597 is 34% of 19,076, which is very close to one-third. The ratio of 1 out of 3 is a good estimate of the percentage.

· The statement is incorrect because the reference value is the number of teens killed, not all teen girls. It would be correct to say that 34% of teens killed in car crashes are female.

· The statement is incorrect because 6,597 is 34% of 19,076, which is very close to three-tenths. The ratio of 1 out of 3 is not a good estimate of the percentage.

#5 Points possible: 20. Total attempts: 5

A teacher has collected data on the grades his students received in his two classes. The tables below show two different ways to represent the same data as percentages.

Table 1
Grades	A	B	C	D	F
Morning Class	12.5%	25.0%	37.5%	6.3%	18.8%
Afternoon Class	14.3%	20.0%	37.1%	8.6%	20.0%

 

Table 2
Grades	A	B	C	D	F
Morning Class	44.4%	53.3%	48.0%	40.0%	46.2%
Afternoon Class	55.6%	46.7%	52.0%	60.0%	53.8%

 

a. Which table could be used to find out what percentage of the students who received an A are in the morning class?      

b. Which table could be used to find out what percentage of the students in the morning class received an A?      

c. What are the reference values in Table 1?

· The number of students in a certain class.

· The number of students who got a certain grade.

· The number of students in a certain class who got a certain grade.

· The total number of students in both classes.

d. What are the reference values in Table 2?

· The number of students in a certain class.

· The number of students who got a certain grade.

· The number of students in a certain class who got a certain grade.

· The total number of students in both classes.

#6 Points possible: 25. Total attempts: 5

Cholera, a serious intestinal disease, broke out in London in the mid-19th century. People at that time believed cholera was caused by bad air. A physician named John Snow discovered that 61 victims either used the water pump on Broad Street or lived nearby. His research became the basis for the theory that germs cause disease. In the case of cholera, the germs are transmitted by polluted water.

A vaccine for cholera was developed in the late 1800s. A vaccine is a drug that helps a person become immune to a disease. Scientists studied 818 people to determine the effects of a cholera vaccine. The study lasted from 1894 to 1896.

	Infected	Not Infected
Vaccinated	3	276
Not vaccinated	66	473

Use the information in the table to complete the following four statements. Round to the nearest tenth of a percent.

a. % of those vaccinated were infected

b. % of those not vaccinated were infected 

c. % of those infected were vaccinated 

d. % of those infected were not vaccinated 

e. Which of the following statements are correct based on the information in the table? There may be more than one correct answer. 

· If a person was infected, it was more than 20 times more likely that (s)he was not vaccinated rather than vaccinated.

· A person who was not vaccinated was four times more likely to get cholera than someone who got the vaccine.

· A person who was not vaccinated was 12 times more likely to get cholera than someone who got the vaccine.

· If a person was infected, it was four times more likely that (s)he was not vaccinated rather than vaccinated.

#7 Points possible: 20. Total attempts: 5

A CBS News poll conducted June 10 and 11, 2006, among a nationwide random sample of 651 adults, asked those adults about their party affiliation (Democrat, Republican or none) and their opinion of how the US economy was changing ("getting better," "getting worse" or "about the same"). The results are shown in the table below.

	better	same	worse
Republican	38	104	44
Democrat	12	87	137
none	21	90	118

Express each of your answers as a percent rounded to the nearest tenth (for example, 12.3%).

a. What percent of survey respondents identified themselves as Republicans? %

b. What percent of survey respondents thought the economy was about the same? %

c. What percent of Republicans thought the economy was about the same? %

d. Among survey respondents who thought the economy was about the same, what percent were Republicans? %