Title of Notes: Common Denominators Pg. 18 RS

5 6 What is a Denominator? The bottom part of the fraction represents the total parts of the whole 5 6

The Numerator The top part of the Fraction represents the part that you have 5 6

What is a common denominator? Common denominators are the possible ways that fractions can be used to add or subtract unlike numbers These fractions can only be Added or Subtracted by finding a common language (Common Denominator) or Common multiple

Find common denominator 4 2 x 5 + 3 x 4 2 + = = 3 5 3 x 5 10 + 12 22 = 15 15

We multiplied each fraction by the denominator of the other We multiplied each fraction by the denominator of the other. Let's use letters instead of numbers to show it: This method might be a bit easier at first, but the common denominator you determine might not be the least common denominator. What this means is that, at the end of the addition or subtraction problem, you will have to reduce your fraction to its simplest form.

And because they now have the same denominator, we can add them: This method might be a bit easier at first, but the common denominator you determine might not be the least common denominator. What this means is that, at the end of the addition or subtraction problem, you will have to reduce your fraction to its simplest form.

Finding the Least common denominator 13 1 2 + = 3 7 21 7 2 x 3 1 x 7 6 = = 3 x 7 21 7 x 3 21 Find the multiples of each denominator The multiples of 3 are: 3, 6, 9, 12, 15, 18, 21, 24, 27, 30… The multiples of 7 are: 7, 14, 21, 28, 35, 42…