Applications of Arithmetic with Powers of 10

5 min

Teacher Prep
Setup
Students in groups of 2. Give students 1 minute of quiet work time, followed by partner and whole-class discussions.

Narrative

The purpose of this Warm-up is for students to reason about a real-world situation and consider the essential information required to solve problems (MP4).

Launch

Arrange students in groups of 2. Tell students that the Burj Khalifa is the tallest building in the world and is located in the city of Dubai. Then give students 1 minute of quiet think time, followed by 1 minute to share their responses with a partner. Follow with a whole-class discussion. 

Student Task

What information would you need to answer these questions?

  1. Which is taller, the Burj Khalifa or a stack of the money it cost to build the Burj Khalifa?
  2. Which has more mass, the Burj Khalifa or the mass of pennies it cost to build the Burj Khalifa?

Sample Response

  1. Sample responses: the height of the Burj Khalifa, the cost to build the Burj Khalifa, the denomination of money that would be stacked, the thickness of one unit of the specified denomination
  2. Sample responses: the mass of the Burj Khalifa, the cost to build the Burj Khalifa, the mass of one penny
Activity Synthesis (Teacher Notes)

The goal of this discussion is for students to share their list of information needed to answer the questions. Invite students to share their responses for each question. Record and display the responses for all to see.

Consider asking questions like these to encourage students to reason further about each question:

  • “Why do you need that piece of information?”
  • “How would you use that piece of information in finding the solution?”
  • “Where would you look to find that piece of information?”

If time allows, ask students to make predictions for each of the questions in the Task Statement. Record and display their responses for all to see. 

Standards
Building Toward
  • 8.EE.4·Perform operations with numbers expressed in scientific notation, including problems where both decimal and scientific notation are used. Use scientific notation and choose units of appropriate size for measurements of very large or very small quantities (e.g., use millimeters per year for seafloor spreading). Interpret scientific notation that has been generated by technology.
  • 8.EE.A.4·Perform operations with numbers expressed in scientific notation, including problems where both decimal and scientific notation are used. Use scientific notation and choose units of appropriate size for measurements of very large or very small quantities (e.g., use millimeters per year for seafloor spreading). Interpret scientific notation that has been generated by technology.

25 min