That's a wrap!
Fractions Review
Here are some important facts about fractions you'll need to remember.
Fraction basics
A fraction is a mathematical expression for parts of a whole.
The denominator (bottom number) represents the total number of equal parts in the whole.
The numerator (top number) represents the number of parts of the whole being considered.
Types of fractions
Common fraction: both the numerator and the denominator are whole numbers (such as
).Complex fraction: the numerator and the denominator are fractions (such as
).Proper fraction: the numerator is smaller than the denominator (such as
).Improper fraction: the numerator is larger than the denominator (such as
).
Converting to improper fractions
Multiply the denominator by the whole number.
Add the product to the numerator.
The resulting sum is the new numerator.
Leave the denominator as it is.
Reducing fractions
Determine the largest common divisor.
Divide the numerator and the denominator by that number.
Common denominators
Multiply all the denominators in a set of fractions to find the common denominator.
The smallest multiple of the denominators is the lowest common denominator.
Use prime factoring to determine the lowest common denominator.
Adding and subtracting fractions. Always convert to fractions with common denominators first, then add or subtract the numerators and keep the denominator as it is.
Multiplying fractions
Don't convert fractions to common denominators.
Multiply the numerators and the denominators in turn.
Dividing fractions
Don't convert fractions to common denominators.
Write them as two fractions separated by a division sign.
Invert the divisor.
Multiply the dividend by the inverted divisor (reciprocal).
Don't forget!
Always reduce the final answer to its lowest terms.
If the fraction is improper, convert to a mixed number. Yes! I finally get it! I'm Dominator of the denominators now!