J. W. Riley Home Page District 21 Home Page Alphabetical Index Graphic Credits
Math Trail 2003--The Problem with Prices
Although District 21 attempts to restrict external links to web sites of appropriate educational content, neither the school or School District 21 is responsible for questionable or controversial content found through links external to this site.


Earning and spending our hard-earned allowance and savings is a topic that intrigues most of us students. In preparing this series of problems, we considered the cost of specific food items for the Chicagoland region over the past century. During the construction of the word problems, we experimented with presenting information using tables and graphics. We used the QAR (Question Answer Routines) method to determine how to solve the problem.

Most of all, we think these problems are fun because there are some historical facts within the question. We liked writing these problems, particularly when we know the "tricks" to getting the right answer--the use of QAR's! The demand for clear thinking and careful writing were very much in evidence.

Step One: Review the Question and Answer Responses by Taffy Raphael.



Taffy Raphael
target

 

Right There:

 

The information that answers the problem is in the table. You can point to the answer in one of the table's cells.

magnifying_glass Think & Search:

 

The information needed to answer the problem is in the table, however, you might need to add, subtract, multiply or divide to reach the correct answer.

parent with book Author and You:

 

At least part of the information needed to answer the problem is in the table, however, you will need to use your prior knowledge about the topic and add, subtract, multiply or divide to reach the correct answer.

number one On Your Own:

The information needed to solve the problem is not in the table; it is information you must have learned earlier--perhaps in science or social studies. However, the information presented in the table may expand your knowledge of the issues and may help you give a clearer, more specific answer to the problem.

Step Two: Use the Minimum Wage Table to solve the problems below. The type of QAR has been identified.

Year
Minimum Wage
1938 $0.25
1940 $0.30
1950 $0.75
1960 $1.00
1970 $1.60
1980 $3.10
1990 $3.80
1991 $4.25
2000 $5.15

About the Federal Minimum Wage


The federal minimum wage for covered, nonexempt employees is $5.15 per hour. The federal minimum wage provisions are contained in the Fair Labor Standards Act (FLSA). Many states also have minimum wage laws. In cases where an employee is subject to both the state and federal minimum wage laws, the employee is entitled to the higher of the two minimum wages.

The Fair Labor Standards Act (FLSA) establishes minimum wage, overtime pay, record keeping, and child labor standards affecting full-time and part-time workers in the private sector and in Federal, State, and local governments. The FLSA requires payment of the Federal minimum wage to all covered and nonexempt employees. Overtime pay at a rate of not less than one and one-half times the regular rate of pay is required for all hours worked over 40 in a workweek

.US Dept. of Labor http://www.dol.gov/esa/minwage/q-a.htm

moneyEXAMPLE: During the 1960's, a factory worked averaged more than $100 per week for the first in in United States history for working a 40 hour work week.

Problem
QAR
Answer
1. What was the federal minimum wage in 1960? Right There  
2. What was the average pay per hour for a factory worker who earned $100 for a 40 hour week during the 1960's:? Think and Search  
3. What was the difference between his earnings per hour and the minimum wage? Think and Search  
4 If in 1970 a factory worker earning minimum wage put in an extra day's hours during one 40 hour work week, what would s/he earn for that week? Author and You (Hint you need to know that overtime was paid at time and a half and that the work day was eight hours long.)  
5. Does an increase in the minimum wage mean that workers will be able to purchase more goods and services? On Your Own  

Check your answers for this example

Step Three: Use the Chicago Prices Table below to solve the problems students have written. The QAR has not been identified.

Food Basket--Chicago Statistics

1920--1970 Cities where data was collected: New York, Atlanta, Denver, and Los Angeles 1980--National Average, North East, North Central, South, West Area

Data From: The Value of a Dollar: Prices and Incomes in the United States 1860-1999. (2000). Edited by Scott Derks. Lakeville, CT: Grey House Publishing.

Item 1900 1910 1920 1930 1941 1950 1960 1970 1980 1990 2000
Apples, evaporated, per pound*** $0.08       $0.06 $0.14 $0.18 $0.20 $0.65 $0.78 $0.94
Bananas per pound                 $0.35 $0.42 $0.49
Beans, dry, per quart $0.09   $0.12 $0.12 $0.10 $0.15 $0.18 $0.18     $0.60
Beef, fresh, steaks per pound $0.12 $0.20 $0.35 $0.43 $0.38 $0.89 $0.90 $1.09      
Beef, ground, per pound                 $1.85 $1.57 $1.44
Bread, loaf $0.05   $0.12 $0.09 $0.07 $0.14 $0.19 $0.24 $0.48 $0.66 $0.93
Butter, per pound $0.23 $0.36 $0.63 $0.44 $0.41 $0.71 $0.75 $0.87 $1.95 $2.03 $2.48
Cheese, per pound $0.17   $0.42 $0.40 $0.31 $0.51 $0.67 $0.51    
Chickens, per pound $0.11 $0.20 $0.42 $0.32 $0.32 $0.48 $0.39 $0.40 $0.74 $0.85 $1.05
Coffee, per pound $0.13   $0.40 $0.40 $0.25 $0.77 $0.75 $0.94 $2.90 $2.77 $3.03
Cornmeal, per pound $0.02 $0.03 $0.07 $0.07 $0.06 $0.10 $0.13        
Eggs, per dozen $0.18 $0.30 $0.71 $0.41 $0.39 $0.57 $0.55 $0.61 $0.88 $1.15 $0.91
Flour, wheat, per pound $0.02   $0.08 $0.04 $0.05 $0.09 $0.10 $0.11 $0.21   $0.29
Milk, fresh, per quart $0.06 $0.08 $0.15 $0.14 $0.15 $0.21 $0.28 $0.35 $0.54 $0.73 $0.68
Margarine per pound by sticks               $0.31 $0.70 $0.84  
Pork, fresh, per pound** $0.09 $0.18 $0.38 $0.36 $0.35 $0.75 $0.86 $1.01 $1.91 $3.20 $3.28
Pork, salt, bacon, per pound $0.12 $0.28 $0.56 $0.47 $0.37 $0.64 $0.64 $0.99 $1.64 $1.95 $3.12
Potatoes, Irish, per bushel* $0.39   $0.07 $0.04 $0.04 $0.06 $0.08 $0.12 $0.23 $0.34 $0.33
Prunes, dried, per pound $0.08   $0.29 $0.17 $0.11 $0.25 $0.39        
Rice, per pound $0.05   $0.17 $0.10 $0.08 $0.16 $0.18 $0.20      
Sugar, per pound $0.08 $0.06 $0.20 $0.06 $0.06 $0.10 $0.11 $0.13 $0.54 $0.40 $0.42
Tea, per pound $0.48   $0.70 $0.73 $0.82   $0.69 $0.62      
* per pound beginning 1920                      
** pork chops beginning in                      
***fresh after 1940                      

Student Written Problems

baseball player

Problem One:

Johnny’s Trip to the Major League Baseball Game


In 1991, Johnny and five friends wanted to go to the major league baseball game where the Sox were playing against the Cubs. Johnny earned minimum wage of $4.25/hour.

The average cost of a major league baseball game in 1991 was $8.64. However, he wanted to get seats nearer the field and so he paid $12.50 for each seat. He is paying for all of the tickets. How many hours will he have to work at his minimum wage to pay for all the tickets?

Answer

movie camera

Problem Two: Dinner at the White House

A famous movie star, named Max Williams, invited President Franklin D. Roosevelt, his wife the First Lady, Eleanor Roosevelt, Vice-President John N. Garner and the Secretary of State Cordell Hull for dinner in 1941. He bought 2 pounds of apples, 1 quart of beans, 1 pound of steak, 3 loaves of bread, 1 pound of butter, 2 pounds of chicken, 3 pounds of coffee, 2 dozen eggs, 1 pound of flour, 12 quarts of milk, 2 pounds of bacon, 2 pounds of potatoes, and 1 pound of sugar.

1. How much money would the movie star have spent if he bought these items in 1941?

2, How much money would the movie star have spent if he bought the same things and the same amount of the food in 2000?

3. What is the difference in cost between the items purchased in 1941 and 2000?

Answer

eggs

Problem Three: Easter Egg Hunt

A billionaire, chicken farmer, is having a Easter Egg Hunt. Everyone at the party will be asked to locate chicken eggs hidden in his mansion and property. There are 100 people coming to the party. Everyone is to find 20 eggs.
He is going to serve bacon and eggs after the hunt is finished. He plans to serve each guest 5 eggs. He needs to buy 10 lbs. of pork and 10 lbs. of sugar. He currently has $10,365 in his bank account.


1. How many eggs does he have to buy for the egg hunt
2 How many eggs does he have to buy to make breakfast?
3. How many eggs does he need in all?
4. How much does his total purchase of eggs cost?
5. How much is his total purchase for the egg hunt and the breakfast?
6. How much remains in his bank account after he pays the bill?

Answer

BBQ

Problem Four: Joe's BBQ

1. How much more did a loaf of bread cost in 2000 than in 1960?

2 Joe Franklin wants to have a BBQ in 1990 for 7 friends to celebrate the Fourth of July. He wants to serve hamburger, apples, bananas, bread, milk and coffee. He will need 1/2 pound of meat for each guest as well as 3 quarts of milk, 5 pounds of apples, 4 pounds of bananas, 2 loaves of bread, and 3 pounds of coffee. How much will the BBQ food cost?

Answer

birthday_person

Problem Five: Allison's Surprise Birthday Cake

Allison is baking a cake for her sister Mary’s birthday who will be 3 years old in 1920. She is inviting 15 of Mary’s friends. Allison needs 5 ingredients for the party cake. If she only has $2.40 and if the total cost for the groceries is exactly $2.40, what 5 ingredients did she buy?

Allison’s Surprise Birthday Cake
cheese 0.42
eggs per dozen 0.71
cornmeal 0.07
tea 0.70
coffee 0.40
flour 0.71
butter 0.63
milk 0.15
sugar 0.20
bread 0.12
beans 0.12
prunes 0.29
pork 0.38
rice 0.17

Answer

Example

Problem
QAR
Answer
1. What was the federal minimum wage in 1960? Right There $1.00
2. What was the average pay per hour for a factory worker who earned $100 for a 40 hour week during the 1960's:? Think and Search $2.50
3. What was the difference between his earnings per hour and the minimum wage? Think and Search $1.50
4 If in 1970 a factory worker earning minimum wage put in an extra day's hours during one 40 hour work week, what would s/he earn for that week? Author and You (Hint you need to know that overtime was paid at time and a half and that the work day was eight hours long.) $83.20
5. Does an increase in the minimum wage mean that workers will be able to purchase more goods and services? On Your Own

A NOTE OF CAUTION:

How can we find prices of popular items through the centuries to make comparison charts?
A "Food Thru the Ages " project sounds wonderful! Unfortunately, this is not a simple task. Determining accurate historic values of consumer goods is a complicated economic process--one which must factor in regional differences, inflation, labor costs and personal
income. To make international comparisons one must also study the evolution of monetary systems and foreign exchange rates. This is why (for example) it is impossible to draw a simple chart of bread prices through the ages across all cultures. If you want to
compare your local prices from one decade to another you will need to factor in the Consumer Price Index for your area. Numbers are supplied by the U.S. Department of Labor

Morris County Library's Food Timeline
http://www.gti.net/mocolib1/kid/foodfaq5.html#compare

Answer to Problem One

To get this answer we found out that since Johnny was going to pay for 5 other people and himself he would have to pay for six people so he would have to buy 6 tickets. So we did 6*$12.50=$75.00.

Now we had to figure out how long he would have to work to get that much money. To do that we did guess and check strategy. Our first guess was 20 hours * $4.25 = $85.00. That was too much money. Then we lowered it to 17 * $4.25 which was $72.25. That was too little. Then we tried 18 * $4.25 which was $76.50 that was $1.50 too much. ($76.50-75.00 = $1.50)

He will need to work at least 19 minutes of an additional hour to pay for the tickets. Therefore he had to work 18 hours and 18 minutes and 45 seconds. Realistically, he would work 18 1/2 hours.

Answer to Problem Two

1. Add the cost of the items, multiplying by the number of items purchased. $6.10

  1941 2000
2 pounds of apples $0.12  

1 quart of beans

$0.10  
1 pound of steak $0.38  
3 loaves of bread $0.21  
1 pound of butter $0.41  
2 pounds of chicken $0.64  
3 pounds of coffee $0.75  
2 dozen eggs $0.78  
1 pound of flour $0.05  
12 quarts of milk $1.80  
2 pounds of bacon $0.74  
2 pounds of potatoes $0.08  
1 pound of sugar $0.06  

2. In 2000, the bill was $37.97

  1941 2000
2 pounds of apples $0.12 $1.88

1 quart of beans

$0.10 $0.60
1 pound of steak $0.38 $1.44
3 loaves of bread $0.21 $2.79
1 pound of butter $0.41 $2.48
2 pounds of chicken $0.64 $2.10
3 pounds of coffee $0.75 $9.09
2 dozen eggs $0.78 $1.82
1 pound of flour $0.05 $0.29
12 quarts of milk $1.80 $8.16
2 pounds of bacon $0.74 $6.24
2 pounds of potatoes $0.08 $0.66
1 pound of sugar $0.06 $0.42

3. The difference in price between 1941 and 2000 is $31.87

Answer to Problem Three

1. Multiply 100 times 20 to find the number of eggs--2000. One hundred people finding 20 eggs each would total 2000 eggs.

2. Multiply 100 times 5 to find the number of eggs 100 people would eat if each ate 5 eggs. The number is 500.

3. Add the answer to questions one and two. The total is 2500.

4. To determine the total purchase price, determine the number of dozen eggs needed. 2500 divided by 12 which rounds to 209 dozen eggs.

To get the total purchase price for the eggs,multiply 209 by $1.15. This totals $204.35

5. To determine the total cost, find the total cost of the pork (10 times $1.95=$19.50) and the cost of the sugar (10 X .40 = $4.00). Add these costs to the cost of the eggs. $204.35 + $19.50 + $4.00 = $263.85

Answer to Problem Four

1. The difference between the price of bread in 1960 and 2000 was $0.74.

2.

Joe's BBQ Grocery List
Item Cost Amount Total
hamburger $1.57 4 pounds $6.28
apples $.78 5 pounds $3.90
milk $0.73 3 quarts $2.19
bananas $0.42 5 pounds $2.10
bread $0.66 2 loaves $1.32
coffee $2.77 3 pounds $8.31

The total cost is $24.10

Answer to Problem Five

Allison’s Surprise Birthday Cake
cheese 0.42
eggs per dozen 0.71
cornmeal 0.07
tea 0.70
coffee 0.40
flour 0.71
butter 0.63
milk 0.15
sugar 0.20
bread 0.12
beans 0.12
prunes 0.29
pork 0.38
rice 0.17

The five ingredients are: eggs, flour, butter, milk, and sugar. The cost of the cake is exactly $2.40

Bibliography:

Mesmer, H.A.E., and Hutchins, E.J. (2002). Using QAR's with charts and graphs. The Reading Teacher, 56, 21-27.

The Value of a Dollar: Prices and Incomes in the United States 1860-1999. (2000). Edited by Scott Derks. Lakeville, CT: Grey House Publishing.

Top

Reviewed, 2003
J. Beyersdorfer