1. BELL WORK (8 minutes) 1. 1. Convert 17 gallons per minute into cups per second. (Round your answer to the nearest hundredth.) 4qt = 1 gal 2 pt = 1 qt 2 cups = 1 pt 2. 2. If the ratio of oil to milk is 3 cups to 5 cups to make brownies, how many cups of milk do you need for 14 cups total? (Use fractions instead of decimals in your answer.) Feb 25, 2008

2. BELL WORK Answers 1. 1. 4.53 cups per second 17 gal x 4 qt x 2 pt x 2 cups x 1 min 1 min 1 gal 1 qt 1 pt 60 sec 2. 2. 8 ¾ cups of milk 3 5 = m_ 5 8 14 milk (PART) Total in jar (WHOLE) 5 x 14 = 8m 70 = 8m m = 8.75 cups of milk oil milk

3. BELL WORK (8 minutes) 1. 1. Use the Substitution Method to solve: 3/2 y = 4x + 3 12y – 12x = 19 2. 2. If the ratio of oil to milk is 3 cups to 5 cups to make brownies, how many cups of milk do you need for 14 cups total? (Use fractions instead of decimals in your answer and use the algebraic method to solve.) Feb 25, 2008

4. BELL WORK Answers 1. 1. (– ¼, 4/3) See white board for solutions. 2. 2. 8 ¾ cups of milk 3 5 = 14 – m 5 8 14 milk (PART) Total in jar (WHOLE) 5 x 14 = 8 (14-m) 70 = 112 - 8m 8m = 42 m = 8.75 oil milk

5. Homework Questions Exit Slip at the end of the day Exit Slip at the end of the day Data Collection Method Data Collection Method Translating Linear Relationships Translating Linear Relationships Solving one-step & two-step equations Solving one-step & two-step equations Test on Friday!! Test on Friday!! Copy down dates if you still have not Copy down dates if you still have not

6. Homework Questions Exit Slip at the end of the day Exit Slip at the end of the day Data Collection Method Data Collection Method Graph Systems of EQNs Graph Systems of EQNs Substitution to solve Systems of EQNs Substitution to solve Systems of EQNs Determining EQN from a Graph Determining EQN from a Graph Test on Friday!! Test on Friday!! Copy down dates if you still have not Copy down dates if you still have not

7. 8.11.2 Judge validity of data based on data collection method Judge validity of data based on data collection method

8. 8.12.1 & 8.13.1 Recognize situations appropriate for scatterplots Recognize situations appropriate for scatterplots Make conjectures about possible relationships based on scatterplots Make conjectures about possible relationships based on scatterplots

9. If I study longer, will I get a better score? When we use scatter plots: when we have a lot of data when we are trying to figure out how much one variable affects another variable. EXAMPLE: How much does studying longer affect my score? They look like line graphs without connecting the points. The relationship between the two variables is called the correlation (r). You won’t have to know how to calculate correlation (r) until you take a statistics course.

10. Scatter plots

11. But you will have to know… The 3 types of correlation and what they look like: 1. Positive Correlation: As one variable gets bigger, the other one does, too As one variable gets bigger, the other one does, too Sound familiar? (Positive Slope) Sound familiar? (Positive Slope) This is a Perfect Positive Correlation This is a Perfect Positive Correlation EXAMPLE: Amount of money spent & amount of people who go to the movies EXAMPLE: Amount of money spent & amount of people who go to the movies

12. Not so perfect… The positive correlation is The positive correlation is not as perfect here. weak but you can still see it. EXAMPLE: Number of hours you study & grade you receive (different students will get slightly different results)

13. 2. Negative Correlation: As one variable gets bigger, the other one gets smaller As one variable gets bigger, the other one gets smaller Sound familiar? (Negative Slope) Sound familiar? (Negative Slope) This is a Perfect Negative Correlation This is a Perfect Negative Correlation EXAMPLE: Speed of a car & Amount of time it takes to get to its destination EXAMPLE: Speed of a car & Amount of time it takes to get to its destination

14. Not so perfect… The negative correlation is The negative correlation is not as perfect here. weak but you can still see it.

15. 3. No Correlation: No relationship between the variables No relationship between the variables This is an example of NO Correlation This is an example of NO Correlation EXAMPLE: Cost of school lunch & time you spend on the internet EXAMPLE: Cost of school lunch & time you spend on the internet

16. So what kind of correlation is this? If I study longer, will I get a better score? If I study longer, will I get a better score? line of best fit helps you find the direction of correlation and determine its slope or EQN

17. Classwork & Exit Slip