See also the
Dr. Math FAQ:
3D and higher
Browse Middle School Fractions & Percentages
Stars indicate particularly interesting answers or
good places to begin browsing.
Selected answers to common questions:
Finding a least common denominator (LCD).
Comparing/ordering fractions; equivalent fractions.
Improper fractions and mixed numbers.
Converting fractions to/from decimals.
Fractions and repeating decimals.
Finding a percentage.
- Fraction Multiplication and Division [02/10/2001]
How do you do calculations like 2 1/10 * 7 5/8 or 27/30 over 75/100?
- Fraction Problems [4/25/1995]
I am having trouble with some fractions and fractional equations.
- Fractions, Improper Fractions, Mixed Numbers [02/01/1997]
How do you turn an improper fraction into a mixed number?
- Fractions in the SI System? [11/07/2001]
When using metric can 4 cm and 5 mm be written as 4 1/2 mm?
- Fractions of Musical Notes [10/14/1997]
How many notes are in two sixteenth notes plus eighth notes with five
- Fractions with Repeating Decimals [02/24/1997]
How do you know if a fraction will have a repeating decimal or if it will
- Fraction to Decimal to Percent Conversions [10/29/2001]
My teacher requires us to be able to convert fractions, percents, and
decimals all together rather than converting a percent to a fraction OR a
- 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?
- Improper Fractions [04/15/1999]
I need help making improper fractions into mixed numbers.
- Inches, Feet, Yards, Miles, and Unit Fractions [01/29/2002]
I need to know if you multiply or divide in changing feet to inches, feet
to yards, miles to yards, feet to miles, yards to miles, yards to feet.
- Least Common Multiple [3/29/1996]
I have a question about how to find the least common multiples from a set
- Making Fractions into Percentages [04/30/2003]
What percentage is 3/5?
- Markups and Discounts [02/12/2002]
What is the correct way to mark up or discount a product?
- Multiplying and Dividing Fractions [01/23/2001]
We are trying to figure out how to understand division and multiplication
- Multiplying Fractions [04/11/1999]
The basics, with a step-by-step example.
- Multiplying Fractions [02/06/2001]
I need help solving 8/9 * 3/5. What is cross-cancelling?
- Multiplying Mixed Numbers [05/28/1998]
Explaining and illustrating how to multiply fractions and mixed
- Origin of the Percent Symbol [02/12/2002]
Where did the percent symbol originate?
- Percentage as Standard for Comparison [05/12/2003]
How can you have more than 100% of something?
- Percentage Increase in Cost of Eggs [8/4/1996]
When eggs went from 17 to 39 cents, by what percent did the price
- Percentage Increase vs. Percentage [05/13/2003]
If there were 10,000 claims in 2001, and that is a 300 percent
increase since 1999, how many claims were there in 1999?
- Percentage of Increase [7/23/1996]
What is the percent of increase when you go from 96 to 256?
- Percentage Problems [01/20/1998]
What number is 25 percent of 24? 24 is what percent of 25? 24 is 25
percent of what number?
- Percentages to or from Fractions [04/04/1997]
How do you convert between percents and fractions?
- Percentage Target (Projection) [07/24/2003]
I am trying to work out percentage difference between a given figure
and a projected figure in the future.
- Percent Change, Increase, Difference [07/15/1997]
How do you find the percent difference between two numbers? What about percent change and percent increase?
- Percent Problem [5/21/1995]
What percentage of 76 is 27?
- Percent vs. Percentage [08/17/2002]
What's the difference between percent and percentage?
- Ratios as Fractions [01/26/1997]
How do you put ratios into simplest form?
- Reciprocals [12/19/1996]
What is the use of reciprocals?
- Simplifying Expressions with Fractions [9/2/1996]
How do I simplify 9(-1/7)(1/3)(-28) ?
- Simplifying Fractional Equations [4/4/1996]
I am supposed to perform the indicated operations and express results in
lowest terms: 1: ((x^2 - 2xy + y^2) / 6xy) *
((3x^2y^2) / (x^2 - y^2)) = ?
- Simplifying Fractions [12/08/2002]
Finding and eliminating (cancelling) prime factors.
- Turning a Repeating Decimal into a Fraction [10/18/2002]
How do I make a decimal like .063490634906... into a fraction?
- Unit Analysis and Conversion Factors [02/01/2003]
How to convert the following? 7.5 x 10^4 nm to kilometers; 3.9 x 10^5
mg to decigrams; 2.21 x 10^-4 dL to microliters.
- What is a Significant Digit? [12/25/2001]
I came across a question asking for an answer with no more than "2
significant digits" - can you please explain what a significant digit is?
- Why Divide Fractions? [11/5/1994]
Where, in this wide world of ours, would one divide fractions? For
example: 3 2/5 / 7/8. Can you give me a real life example?
- 1/x = x% [04/16/2001]
For what value of x does 1/x = x% ?
- 34 is 51 Percent of J [11/12/2001]
A hint about problems that use the word "of."
- 3 Methods for Finding Least Common Denominator [02/04/1998]
My fifth graders are having a very difficult time understanding how to
get the least common denominator. Any shortcuts?