1 / 13

Making Sense of Sensible (?!?) Rounding

Making Sense of Sensible (?!?) Rounding. Jojo Uichanco / Lukas van Veen. “How much?”. “HOW MUCH?” involves a form of measurement : no sensible rounding necessary. How much did he spend? How much sleep did you get?. “ How many ?”. Answer “HOW MANY?”

sawyer-summers
Download Presentation

Making Sense of Sensible (?!?) Rounding

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Making Sense of Sensible (?!?) Rounding Jojo Uichanco / Lukas van Veen

  2. “How much?” • “HOW MUCH?” involves a form of measurement : no sensible rounding necessary. • How much did he spend? • How much sleep did you get?

  3. “How many?” Answer “HOW MANY?” with a WHOLE number by rounding sensibly. • How many students does it take to change a light bulb?

  4. The framework • Sensible rounding always asks: “How many?” • Need in the problem  Round down • Need in the question  Round up

  5. Example 1. • A taxi can carry up to four passengers.How many taxis do we need to carry 13?13 ÷ 4 = 3.25 • Round down or up?

  6. 3.25Can 3 taxis carry 13 students?

  7. 3 x 4 = 12 students Need is in the question: round up 4taxis can carry 13 students

  8. Example 2.Let’s make (or bake) a cake • Hessa needs four eggs to make a cake.How many cakes can she make with 11 eggs?11 ÷ 4 = 2.75

  9. 2.75Can Hessa make three cakes?3 cakes x 4 eggs  12 eggsNeed is in the problem: round downWith 11 eggs Hessa makes 2 cakes

  10. Example 3. • I need five meters to make a dishdasha.How many dishdashas can I make with 14 meters?14 ÷ 5 = 2.8Two or three?

  11. Need is in the problem: round down • I can make 2 dishdashas

  12. Watch out!!! • A pizza is cut into six slices.Khalid has 20 slices.How many pizzas does Khalid have? • 3 1/3 • A pizza is cut into six slices.Khalid has 20 slices.How many whole pizzas does Khalid have? • 3

  13. Watch out!!! • A box holds twelve eggs. How many boxes are needed for 25 eggs?Round up:3 • A box holds twelve eggs. How many full boxes can be made with 25 eggs? Round down: 2

More Related