2.1+Adding+on+a+Number+Line+0910

SM
 * 18/04/2010

Big idea:** Negative numbers help us model many real world situations.

How to represent integers in number lines. Notes:** In number lines, positive integers are always to the right while negative integers are always on the left. Vocabulary: integer
 * Essential Question:


 * Problem 2.1: Adding on a Number Line

A. Write the addition sentence.**

1) The addition sentence is -4-3= -7. 2) The addition sentence is +4 - (-3)= 7 3) The addition sentence is -4 + 11= 7 4) The addition sentence is 5+(-8) = -3


 * B. Illustrate each addition problem on a number line, and give the answers.**

Ans.b)
 * 1. -5+8 2. -4+-3 3. -2+-3+10**

2. -4+-6 and -6+-4** 4.6+-7 and -7+6**
 * C. When you add two integers, does the order of the numbers make a difference? Illustrate your answers by showing each of these pairs of sums on a number line.**
 * 1. -5+10 and 10+-5
 * 3. 8+-8 and -8+8

Follow up

1.**You can think of scoring in MathMania as follows: When a team answers a question correctly, a positive integer is added to their score. When a team aswers a question incorrectly, a negative integer is added to their score. For each of the following situation, write an addition sentence that will give the team's score. Assume each team starts with 0 points.** Ans. a) Brainacs= 0+200+(-150) = 50 points b) Aliens= 0+100+(-100) = 0 points c) Prodigies= 0+(-50)+(-100)=250 =100 points
 * a) The Brainacs answers a 300-point question correctly and a 250-point question incorrectly.**
 * b) The Aliens answer a 50-point question correctly and a 50-point question incorrectly.**
 * c) The Prodigies answer a 100-point question incorrectly, a 100-point question incorrectly, and a 150-point correctly.**