Lesson 1: Addition and Subtraction of Fractions

To add or subtract fractions that have the same denominators, we add or subtract the numerators, and the result is recorded over the denominator.

Solve 5/11 + 2/11 = ? 5/11 – 2/11 = ?

If the denominators are not the same, it is necessary to rewrite the fractions so that they have the same denominators.

Solve 1/3 + 2/5 = ? 2/3 – 1/8 = ?

Mixed Number*  The sum of a whole number and a fraction

2 ½ This does not mean 2 multiplied by ½ but instead 2 plus ½.

Mixed Numbers When we add and subtract mixed numbers, we handle the fractions and the whole numbers separately.

Solve 13 3/ /8 = ? 13 3/5 – 2 1/8 = ?

Solve 13 3/5 – 2 7/8 = ?

Lines and Segments A mathematical line has arrowheads on both ends to emphasize that the line goes on and on in both directions.

How do we label this Line?

Line Segment  A part of a line.  Contains the endpoints and all points between the endpoints.

How do we label this line?

If we use two letters without the overbar, we designate the length of the segment. (Practice Problem)

Practice: Solve: 10/11 – 5/6 + 1/3 = ?

Practice: Segment AC measures 10 ¼ units. Segment AB measures 4 3/7 units. Find BC.

Homework #1-30 Due Tomorrow