4.1Rising+and+Falling+Temperatures

25/4/09 AB __ Essential Question #4: How do I multiply and divide integers? __ __ Notes: __ None Qa1) Suppose the temperature changed by an average of +3 degrees per hour for a 10 hour period. Copy and complete the table below, and use it to find the total temperature change for the five hours. Ans: Ans)15 degrees because 3 degrees times 5 is 15 degrees. For the intire 10 period is 30 degrees because 10 times 3 is 30. Ans) Ans) The first 5 hours is -15 because (-3 x 5= 15) The first 10 hour period is -30 because (-3 x10=-30) Ans)1. Addition sentences are : a)+2+(+2)+(+2)= +6 b)-3+(-3)= -6 c)-2+(-2)+(-2)+(-2)= -8
 * Big Idea:** Negative numbers help us to model many real world situations.
 * Number of hours || 1 || 2 || 3 || 4 || 5 ||
 * Total Temperature Change || 3 degrees || 6 degrees || 9 degrees || 12 degrees || 15 degrees ||
 * Q2) Write a multiplication sentence that represents the total change in temperature for the first five hours. Write a multiplication that represents the total change in the temperature for the entire 10 hour period.**
 * QB1) Suppose the temperature changed by an average of -3 degrees per hour for a 10 hour period. Copy and complete the table below, and use it to find the total tempreture change for the first 5 hours.**
 * Number of hours || 1 || 2 || 3 || 4 || 5 ||
 * Total temperature change || -3 || -6 || -9 || -12 || -15 ||
 * QB2) Write a multiplication sentence that represents the total change in temperature for the entire 10 hour period.**
 * QC1**)**Write the addition sentence illustrated by each diagram below.**
 * 2)** **Write the multiplication sentence illustrated by each diagram below**

2)Multiplication sentences are : a) 2x3=6 b)-3x2= -6 c) -2x4= -8 Ans) QE) Find each product. 1. -20 2.-80 3.-80 4.-20
 * QD) Make up a situation about temperatures that can be expressed as 4x -10**
 * # of hours || 1 || 2 || 3 || 4 ||
 * Total temperature change || -10 || -20 || -30 || -40 ||

Ans)1) At 1:00 P.M the tempreture was 16 F 2)At 10:00 A.M. the temnpreture was 40 F Ans) No because every time we multiply a positive and a negetive number we always get a negetive value. Example: -5x3 = -15
 * Follow up**
 * 1. Suppose the tempreture changed by an answer of +2 degrees per hour from its low of -4 F at 3:00 A.M. What was the tempreture at 1:00 P.M.?**
 * 2. Suppose the tempreture changed by an average of -1.5 degrees from its high of +25 F at noon. What was the tempreture at 10:00 P.M.?**
 * 3. When you add a positive integer and a negitive integer, you sometimes get a positive result and sometimes get a negetive results. Is the same true when you multiply a positive integer and a negetive integer? Explain.**

