Transcript Combining Signed Numbers

Reducing Fractions
Reducing Fractions
Fractions are not considered to be in simplest form
unless they are reduced. Reducing means that the
numerator (top) and denominator (bottom) have no
common factors.
For example:
2 2 1 1


4 2 2 2
In this case, both top and bottom could be divided
by 2 to make the numbers smaller.
Chop, chop, chop
What if you’re not sure what number would go into both?
One approach is to just start chopping away:
120 12 10 12 3  4 3

 

160 16 10 16 4  4 4
Factor Trees
What if you’re not sure what number would go into both?
Another approach is to use a factor tree:
120
12 10 pick any factors you think of
4  3  2  5 keep going until you have all primes
2  2 3 2 5
2  2  2  3  5 put them in numerical order
Factor 160
What if you’re not sure what number would go into both?
Another approach is to use a factor tree:
160
16 10 pick any factors you think of
4  4  2  5 keep going until you have all primes
2  2  2  2  2  5 put them in numerical order
Cancel
What if you’re not sure what number would go into both?
Now put the factors back in the fraction and cancel
120
2  2  2  3 5
2  2  2  3 5
3



160 2  2  2  2  2  5 2  2  2  2  2  5 4
Calculator
If you have a calculator with a fraction key it will do it
for you!
Reducing Fractions
Fractions are not in simplest
form until you have eliminated
all of the common factors in the
numerator and the denominator.