Real Life Fractions
http://www.ed.gov/pubs/EarlyMath/8.jpg
When do we use fractions?




Cooking
Measurement
Telling time
Money
What is a fraction?
 Fractions show part of something. Such as
pieces of a pizza, part of an hour, half a
pound, a quarter of an dollar.
 The top of the fraction is the numerator. It
tells the pieces.
 The bottom of the fraction is the
denominator. It tells how many make up a
whole.
What the fraction looks like.
Numerator
1 Part
Denominator 2 Whole/All parts
Equivalent Fractions
Sometimes we can write a fraction more than
one way. If we have 4 out of 6 slices of
cake left we can write our fraction two
ways, because 4/6 = 2/3.
4/6 is shaded and also
2/3 is shaded.
http://www.mathleague.com/help/fractions/fractions.htm#whatisafraction
Equivalent Fractions
Look to see if the numerator and denominator
have a like factor. If they do, we can
simplify the fraction. Examples: 3 and 9
have like factors, so 3/9 = 1/3.
Adding Fractions
When we combine units the denominators
need to bee the same. Meaning, when we
add fractions, we have to have like
denominators.
2 +3=5
3 +6 = 9
7 7 7
11 11 11
Common Denominators
 If you are not given like denominators, you
have to find the least common denominator.
 Take your denominators, and factor them
out.
 Then, match up any common denominators.
Pull one factor for each match. For
example 2x2=4 and 2x3=6, so pull out one
2 since there is a 2 in each.
Common Denominators
 Next, account for the numbers not matched
up. So for 4 and 6, we would account for
the 2 and 3 that did not match up.
 We would multiply all the numbers
together. Meaning the 2 and 3, with the
number we took out earlier, which was a 2.
 So from 2 x 2 =4 and 2 x 3 = 6, our
denominator would be 2x2x3=12.
Find the common denominator
when given these two fractions.
 1+2 = ?
3 9
?
Remember your denominators are 3 and 9.
If you put 9 you are right!
3 x 1 = 3 and 3 x 3= 9
One 3 matches up, so take it out. The rest
does not, so take the remaining 3 and 1 out.
3x3x1=9
How to change into equivalent
fractions.
Once you have found your common
denominator, you need to find the
equivalent fractions.
1 = 3 Because we need 9 as our denominator,
3 9 we multiply 3 x 3 to get 9. What ever
we multiply the denominator by, we do the
same to the numerator.
If our denominator has to be 12,
try to find the numerator.
3= ?
4 12
If you said 9 you are correct!
3= 9
4 12
Because 4 x 3 = 12, you have to
multiply the top by 3 also.
3x3=9
Once you have like denominators
you can add.
Solve 3 + 2
9 9
=
?
?
Exactly!
3 +2 =5
9 9 9
Try this one next:
2+1=
3 5
Remember you need to find like
denominators.
Did you get:
2 + 1 = 13
3 5 15
Why? Your denominator has to be 15,
because 3 and 5 have no like factors,
so multiply 3 x 5 = 15.
10 + 3= 13
15 15 15
Congratulations!
You are on your way to mastering fractions.
Works Cited
Picture on Page 1
 http://www.ed.gov/pubs/EarlyMath/8.jpg
Picture on Page 5
 http://www.mathleague.com/help/fractions/fractions.htm#
whatisafraction
All other pictures clip art.