Adding Fractions With Like and Unlike Denominators

Presented

By

Nathaniel Thompson

What is a fraction?

A fraction is a representation of a part of a whole unit. A fraction has two parts, a numerator and a denominator.

23

• The top number (2) is called the numerator.

• The bottom number (3) is called the denominator.

• This fraction represent two thirds of the whole unit.

Adding Fractions With Like Denominators

7 + 6

15 15

• When adding fractions with denominators that are the same, simply add the two numerators.

• The denominator remains the same.

7 + 6 =

15 1513

15

Adding Fractions With Unlike Denominators

1 + 1

8 4

• Before fractions with different denominators can be added, the denominators must be changed so that they are the same.

• You must find a common denominator.

Adding Fractions With Unlike Denominators

1 + 1

8 4

• To find the least common denominator, find the least common multiple of 4 and 8

4: 4, 8…

8: 8…

• The least common denominator of 4 and 8 is 8.

Adding Fractions With Unlike Denominators

1 + 1

8 4

• Since the denominator of the first fraction is 8, the first fraction remains the same.

• The denominator of the second fraction (4) must be changed to 8.

Adding Fractions With Unlike Denominators

1 + 1x2

8 4x2

• Because the denominator (4) is multiplied by 2, the numerator (1) must also be multiplied by 2.

Adding Fractions With Unlike Denominators

1 + 2

8 8

The New Addition Problem Becomes

Adding Fractions With Unlike Denominators

1 + 2 =

8 8 3

8

The End