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Middle School Archive

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100 Percent of Daily Allowance of Iron [09/30/2001]

A common foodstuff is found to contain .00125% iron. The serving size is 87.0 grams. If the recommended daily allowance is 18mg of iron, how many servings would a person have to eat to get 100% of the daily allowance of iron?

Acid Concentration, Heating Bill [7/6/1996]

1) A pharmacist has 8 liters of a 15 percent solution of acid. How much distilled water must she add.... 2) By installing a $120 thermostat, a family hopes to cut its annual heating bill...

Age and Money [12/13/1994]

Frank is eight years older than his sister. In three years he will be twice as old as she is. How old are they now? (and other similar problems)

Backward Through the Steps [5/20/1996]

Can you show strategies for solving this baseball card word problem?

Blending Seed [09/27/1998]

How much of $0.65/lb seed does a dealer need to combine with 200 lbs of $0.45/lb seed to make a $0.55/lb blend?

Calculating Income vs. Sales [3/26/1996]

A factory owner knows that some of her expenses are going to occur regardless of how many items she makes. These are fixed costs and total $3000 per week...

Conversions [3/17/1995]

Nancy ran a distance of 3.8km in 55 min. Calculate her speed in kilometers per hour and metres per second.

Cost of Cleaning a Building [07/03/2003]

If I clean a 3200 square foot building five nights per week for a sum of $575.00 per month, what is the cost per square foot?

Derfs and Enajs: Algebra and Venn Diagrams [03/09/2003]

All Derfs are Enajs. One-third of all Enajs are Derfs. Half of all Sivads are Enajs. One Sivad is a Derf. Eight Sivads are Enajs. The number of Enajs is 90. How many Enajs are neither Derfs nor Sivads?

Diesel or Gasoline Engine? [10/16/1996]

You can buy a car with a diesel engine for $427.65 more than the same car with a gasoline engine...

Dimensional Analysis [10/06/2001]

Mr. R wants to give all of his chemistry students enough chocolate to make them goofy for the rest of the day. It's a known fact that it takes 47 chocolate chips to make a student goofy...

Employee Pay Schedule [07/12/2003]

For a particular job, Moe should get 40% of the gross pay, Larry should get 30%, and Curly should get 30%, assuming they all work the same number of hours. But how should the money be divided if they work different numbers of hours?

Equations from Word Problems, and Units [05/19/2003]

In 2 1/4 hours the temperature dropped 13 1/9 degrees. How many degrees did the temperature drop per hour? How do I convert this from words into an equation?

Factoring Problems [8/14/1996]

What is the width of an uniform border surrounding a rectangle?

Farmer Crossing a River [09/24/2001]

A farmer is taking his prize lettuce, lion, llama, and pet leviathan (a unique creature that eats llamas and lions unless a lettuce is present) to market...

Finding One Coin of 12 in 3 Steps [8/6/1996]

Given a pile of twelve coins of equal size with one of a different weight, in three weighings find the unequal coin...

Finding Sally's Hourly Wage [11/7/1994]

Sally works at a grocery store. In one week she earned $390 for working 47 hours, of which 7 hours were overtime.The next week she earned $416 for working 50 hours, of which 8 hours were overtime. What is Sally's hourly rate?

Finding the Ages of the Farmer's Daughters [12/21/1995]

A man has three daughters. The product of their ages is 72, the sum of their ages is his house number, and the oldest loves chocolate. What are the daughters' ages?

How Many Boxes? A Diagram [03/20/2003]

There were juice boxes in a cooler. Jared took 1/6 of them. Sara took 1/4 of what was left. Now there are 15 boxes. How many boxes were there to start with?

How Many Chickens and Ducks? [8/16/1996]

A man bought 20 chickens and ducks, with a $2 discount per chicken and 50 cent discount per duck...

How Many Stools? How Many Tables? [12/13/2002]

In their spare time, the Buffalo Bills operations staff members build 3-legged stools and 4-legged tables. Last month they used 72 legs to build 3 more stools than tables.

How much is the dagger worth? [10/12/1996]

A sword and dagger are together worth 300 copper pieces. The sword is worth 200 copper pieces more than the dagger. How much is the dagger worth?

How Much Money is Left? [5/1/1995]

A lady has a certain number of dollar bills in her purse. She has no other money. She spends half the money on a hat and gives $1 to a beggar outside the store. She spends half the remaining dollars for lunch and tips the waiter $2. She then spends half the remaining dollars for a book, and just before she goes home she spends $3 on a hot fudge sundae. She now has $1 left. How many dollars did she begin with?

How Old are Ben and Kris? [10/17/1999]

Five years ago Ben was 2/3 as old as Kris. Ten years from now he will be 5/6 as old as Kris. How old are they now?

How Old is Chris Now? [12/26/2001]

Pat is twice as old as Chris was when Pat was as old as Chris is now. If Pat is 24 now, how old is Chris now?

How to Turn Word Problems into Algebra Equations [6/6/1996]

Where do you put the letters and numbers when setting up algebra equations from word problems?

Least Common Multiple Word Problem [12/10/1996]

Each of three businesses receives different sized cartons of glasses. If all three receive the same number of glasses and none of them receive more than a thousand glasses, how many glasses and cartons are in each shipment?

Least Number of Marbles [2/20/1995]

After a successful game of marbles with three friends, Joe said, "If only I had one more marble, ...." What is the least number of marbles Joe could have had?

Markups and Discounts [02/12/2002]

What is the correct way to mark up or discount a product?

Math Age Word Problem [03/20/2001]

Bob is as old as John will be when Bob is twice as old as John was when Bob's age was half the sum of their present ages...

Math Logic [6/5/1996]

Sally, Ron, Jim, and Meghan are President, VP, Treasurer, and Captain of the cheerleading squad, but not necessarily in that order. Who is what?

Mixing Alcohol, Cable TV Pricing [8/2/1996]

What amounts of 9 percent and 12 percent alcohol do you mix to get 300,000 gallons of 10 percent alcohol? For each 5-cent increase in the monthly subscription price, 4 people will decide not to subscribe to cable TV...

Mixing Milk and Butterfat [09/04/2001]

Milk that has 5% butterfat is mixed with milk that has 2% butterfat. How much of each is needed to obtain 60 gallons of milk that has 3% butterfat?

Number of Quarters [9/11/1996]

Tony has eleven more nickels than quarters. How many quarters does he have if the total value of his coins is $2.65?

Number Puzzle Solved with and without Algebra [12/10/2001]

I am a number. Add 25 to me. Divide the sum by 2. You end with 75. What number am I?

Pencil Costs, Dividing Property [6/25/1996]

1) Drawing pencils cost 8 cents each and colored pencils cost 11 cents each. Two dozen assorted pencils cost $2.16. How many colored pencils are there? 2) A man died, leaving 23 cows to his three children; the eldest child should have 1/2 of the cows...

Radius of a Pizza [8/27/1996]

If a pizza has an area of 30 inches, what is its radius?

Rate of Travel [05/15/2003]

A passenger on a train traveling at 135km/h walks toward the back of the train at a rate of 7km/h. What is the passenger's rate of travel with respect to the ground?

Rates and Proportion [7/11/1996]

If 10 men can build 2 boats in 4 days, how many men are needed to build 5 boats in 2 days?

Renting Bike Safety Equipment [10/09/2001]

The Park Department rents a bike with safety equipment for $5 a day. If you provide your own safety equipment, the bike rental is $3 a day. You could buy equipment at a sports store for $28. How many times must you use the trail to justify buying your own safety equipment?

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