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Selected answers to common questions:
Adding and subtracting fractions.
Finding a least common denominator (LCD).
Comparing/ordering fractions; equivalent fractions.
Improper fractions and mixed numbers.
Converting fractions to/from decimals.
Rounding fractions and decimals.
Fractions and repeating decimals.
- When to Add or Multiply Denominators? [04/02/2001]
When you multiply fractions, you multiply the numerators and then the
denominators. When you add fractions, you add the numerators but not the
denominators. Why the difference?
- Why Cancel? [02/25/2003]
Why do we have to cancel numbers?
- Why Decimal Division Works [04/24/2001]
Can you explain why (not how) the procedure of division with decimals
- Why Does Division Convert a Fraction to a Decimal? [01/04/2009]
Why do you divide the denominator into the numerator to turn a
fraction into a decimal? What is the math behind that process?
- Why Does OF Mean Multiply? [12/04/2001]
I wanted to know why the word "of" means multiplication.
- Why Do We Rationalize Fractions? [11/29/2005]
Why do we have to simplify fractions that have a radical in the
denominator to remove that radical and rationalize the denominator?
Why is that important?
- Why Find the LCM? [10/07/1998]
Where do you use LCMs? How do they apply to real life?
- Why Learn Fractions? [8/13/1996]
What is the point of learning fractions?
- Why Round Decimals? [11/24/1997]
I have to explain to a 5th grader why we would want to round decimals.
- Why the Decimal Point Goes Where It Does [09/21/2003]
My daughter is having trouble understanding why the first place before
the decimal point is 'ones', and the first one after is 'tenths'.
- Why the Decimal Point Moves when Multiplying by 10 [02/11/2005]
I am trying to explain why when you multiply a number by 10 you move
the decimal point over one place to the right, and one place to the
left when you divide by 10.
- Why the Fraction Division Technique Works [11/27/2004]
Why do we need to flip the second fraction when we divide fractions?
- Why We Need Decimals [10/23/1995]
Why do we need decimals?
- Why Were Fractions Invented? [11/26/2007]
An overview of the history of fractions and the purpose they serve.
- Working with Mixed Number Fractions [1/23/1996]
How do I subtract, add, or multiply a mixed number fraction?
- Writing a Percent as a Fraction and Reducing the Result [05/03/2004]
I just can't seem to figure out how to convert a percent into a
fraction, such as 20% = 20/100 = 1/5. All I know is that you put it
into a fraction like 20/100 but after that I get stuck and I just
don't know how to get the answer.
- Writing a Remainder as a Reduced Fraction [08/29/2001]
I have to solve two division problems and write the remainder as a
- Writing Decimals from Words [10/05/1998]
Given a decimal written in words, how do you turn it into a decimal? In
other words, how do you turn the words into numbers?
- Writing Numbers with Hyphens [06/04/2003]
Why do we hyphenate one hundred-millionth, but we don't hyphenate one
- Written Form of Decimals [03/21/2001]
What is the correct way to write decimals?
- Zero Before the Decimal Point? [10/06/2000]
What is the merit of writing the zero before the decimal point in numbers
less than one, for example 0.25?
- Zero in the Denominator [8/14/1996]
What is the value of 4/0 * 0/4?
- Zeros after the Decimal Point [09/17/2001]
I have a group of students who just can't comprehend my explanation of
how 3.70 is equivalent to 3.7 or 3.700 or 3.7000.
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