Today’s Focus: Comparing and Ordering Decimals

1. Today’s Focus:Comparing and Ordering Decimals In real life, when will you ever need to compare or order decimals?

2. Mr. Briganti’s morning of decimals…. It is hard to imagine going for more than a few minutes without seeing decimals. When I got up this morning and ate my breakfast, I noticed that the side of my cereal box read: A 1.2 oz serving of Rice Krispies contains: 2.5 grams of protein2.7 grams of fat I put milk on my cereal and the milk carton’s label read: One cup of milk contains: 3.6 grams protein1.8 grams fat

3. 1 8 2 After eating breakfast I brushed my teeth. The toothpaste tube read 0.24% Sodium Fluoride. But my daughter’s had 0.243%. I got into my car and drove to school. On the way I stopped and bought a coffee, it cost me $1.70 plus a tax of 6% or 0.06 (the tax is $.102 ). When I arrived to school I looked at my car’s odometer and saw that I had traveled 18.2 miles. I have seen decimals in 8 places and I haven't even made it to math class yet!!

4. Real Life Scenarios Comparing and Ordering Decimals

5. Real life scenario #1: Temperature • Your normal body temperature is 98.6 degrees Fahrenheit One morning you don’t feel so well. Your parent takes your temperature. Three temperature readings are taken in an hour. Place the readings in order from least to greatest? 98.60, 97.8, 99.01, 99.09 97.8 98.60 99.01 99.09

6. Real life scenario #2: Shopping / Food Purchases • Double Cheeseburger: $ .99 • Big Mac Value Meal: $ 4.79 • Chicken McNuggetts Meal: $ 3.80 • Small Drink: $ .99 • McFlurry: $ 1.97 • Salad: $ 4.80 • 2 Cheeseburger Meal: $ 3.70 • Ice Cream Cone: $ .87 Which menu item is the most expensive? The least expensive? Fill in the following with “greater than” >, or “less than” < < > Big Mac Value Meal ____ Salad Small Drink ____ Ice Cream Cone < > McFlurry ____ Two small drinks McFlurry ____ Double Cheeseburger

7. Real life scenario #3: Sports The table below shows the times of four students who ran the 25 yard dash in their gym class. Who ran the dash in the fastest time? How do you know?

8. D C A B E 3.234 3.401 3.041 3.140 3.104 Real life scenario #4: Library Books Put the following books in order from highest to lowest….. B, A, D, E, C

9. Real life scenario #5: Available Memory You want to purchase a new iPod Nano. Which one below has the most amount of memory? A B C D E 40.234 GB 40.09 GB 40.95 GB 40.99 GB 39.999 GB

10. Real life scenario #6: Grade Point Average Which GPA would you like most? A. Three and seventy-two hundredths B. Three and seven thousandths C. Three and seven hundredths D. Two and ninety nine hundredths 3.72 3.007 3.07 2.99

11. A Quick Review of the Strategies

12. Strategy #1: Comparing Decimals • When we compare we use terms such as: • Less than < • Greater than > • Equal to = • Comparing decimals is similar to comparing whole numbers. • 45 < 47 4.5 < 4.7 • 150 > 105 15.0 > 10.5 • When we compare decimals we use place value or a number line.

13. Strategy #2: Use Place Value Hundreds Ones Thousands Tens Tenths Hundredths Thousandths

14. Strategy #3: Using a Number Line 42.0 42.1 42.5 Numbers to the right are greater than numbers to the left. Since 42.5 is to the right of 42.1 we have: 42.5 > 42.1

15. Strategy #4: Using Grids = 0.60 0.6

16. Strategy #5: Include an Invisible Zero 15, 14.95, 15.8, 15.01 • Include zeros so that each number has the same number of decimal places 15.00 14.95 15.80 15.01

17. Are you ready to try some on your own?

18. Center #1 Order these numbers from greatest to least 35.06, 35.7, 35.5, 35.849 Show your work by using the following strategies: Place Value Including an Invisible Zero

19. Center #2 In which square is the amount shaded 0.25? A C B D

20. Center #3 Which square is the amount shaded 0.7? A C B D

21. Center #4 A small piece of gold weighs 0.162 grams. What is the word form of this number? • one hundred sixty-two tenths • one hundred sixty-two hundredths • one and sixty-two thousandths • one hundred sixty-two thousandths

22. Center #5 A small piece of gold weighs 0.176 grams. What is the word form of this number? • one hundred seventy-six thousandths • one hundred seventy-six hundredths • one and seventy-six thousandths • one hundred seventy-six tenths

23. Center #6 A golf ball weighs 1.62 ounces. What is the word form of this number? • one and sixty-two hundredths • one hundred sixty-two hundredths • one and sixty-two thousandths • one hundred sixty-two thousandths

24. Center #7 Which shows fifty-one and eleven hundredths? • 51,011 • 5,011 • 51.11 • 51.011

25. Center #8 A 0 2 1 • Which number should be written at point A? • 1.04 • 1.4 • 0.14 • 2.4

26. Center #9 A D B C 0 2 1 • At which point should be 1.15 be written? • Point A • Point B • Point C • Point D

27. Center #10 The table below shows the times of four students who ran the 50 yard dash in their gym class. Who ran the dash in the longest time?

28. Center #11 The table below shows the times of four students who ran the 50 yard dash in their gym class. Who ran the dash in the fastest time?

29. Center #12 Mrs. Norcel purchased three kinds of supplies at the supply store. The weights for each supply are shown in the table below. What is the total weight of the supplies she purchased? • 23.00 pounds • 33.86 pounds • 3.86 pounds • 13.86 pounds

30. Center #13 • Which numbers are in order from LEAST to GREATEST? • 1.842, 1.358, 1.675 • 0.561, 5.618, 5.96 • 2.057, 3.1, 3.006 • 4.703, 4.525, 4.207

31. Center #14 • Which numbers are in order from LEAST to GREATEST? • 2.342, 2.358, 23.58 • 0.234, 2.342, 2.034 • 0.023, 3.2, 2.243 • 1.001, 0.111, 1.110

32. Center #15 Order these numbers from greatest to least 45.16, 45.7, 45.5, 45.749 Show your work by using the following strategies: Place Value Including an Invisible Zero