Download FRACTION OVERVIEW

FRACTION OVERVIEW
1.
2.
3.
TO WRITE A MIXED NUMBER AS AN IMPROPER FRACTION:
Multiply the whole number part of the mixed number by the
dominator of the fraction.
Add the numerator of the fraction to the product from Step 1.
Write this sum as the numerator of the improper fraction over
the original denominator.
5 72 
5  7  2 35  2 37


7
7
7
17
2
5
3
3
TO WRITE AN IMPROPER FRACTION AS A MIXED NUMBER OR A
WHOLE NUMBER:
1.
Divide the denominator into the numerator.
2.
The whole number part of the mixed number is the quotient.
The fraction is the remainder over the original denominator.
quotient
5
3 17
15
2
remainder
orginal denominator
Fractions that represent the same portion of a whole are called
equivalent fractions.
3
4
A fraction is in simplest form or lowest terms when the numerator and
the denominator have no common factors other than 1.
Write in simplest form
1
This is often called reducing the fraction to its lowest terms. Fractions
must always be reduced to lowest terms unless the directions
specifically state otherwise.
12
16
30
:
36
1
30
2  3  5
5


2  2  3  3
6
36
1
1
Multiply:
To multiply two fractions, multiply the numerators and multiply the
denominators.
7 3 7  3 21
 

8 5 8  5 40
1
3 1 3 1
3 1
1
 


4 6 4  6 4  3  2 8
1
1 1
7 1
7
2    
3 9
3 9
27
Drl/morgan-krick/fractionoverview
Two numbers are reciprocals of each other if their product is 1.
The reciprocal of
5
3
is
3
5
To divide two fractions, multiply the first fraction by the reciprocal of
the second fraction.
Divide:
Fractions that have the same denominator are called like fractions.
2 5
1
6
and , and
3
7
3 7
To add or subtract like fractions, combine the numerators and place
the sum or difference over the common denominator.
2 3
5
 
7 7 7
7 4
3
 
8 8
8
TO ADD OR SUBTRACT FRACTIONS WITH UNLIKE DENOMINATORS
Add:
3
7
3 9 3  9 27
   

10 9 10 7 10  7 70
Add the numerators
Keep the common denominators
Subtract the numerator
Keep the common denominators
3
2

20 5
Step 1. Find the LCD (least common denominator)
Step 1. The LCD is 20.
Step 2. Write equivalent fractions with the LCD as
denominator.
Step 2.
2 2 4 8


5 5  4 20
Step 3.
3 2 3 8
11
  

20 5 20 20 20
Step 4.
11
is in simplest form.
20
Step 3. Add or subtract the like fractions.
Step 4. Write the result in simplest form.
Drl/morgan-krick/fractionoverview