Lesson 3

Multiplying by Multiples of Ten

Est. Class Sessions: 1–2

Daily Practice and Problems

Teacher Notes
X

TIMS Task

Refer students to the Addition Strategies Menu and Subtraction Strategies Menu in the Student Guide Reference section.

Subtracting across zeros using the traditional algorithm is often inefficient. Students can use counting up and counting back strategies to solve A–C. For example, to solve C, they can subtract 100 from 65,800 to get 65,700; add back one to get 65,701; then subtract 5000 to get 60,701.

  1. 89,198
  2. 79,000
  3. 60,701
  4. 9163
  5. 78,884
  6. 100,374

Possible estimation strategy for F:

J. Adding and Subtracting for Practice

Do the following problems mentally. Be ready to explain how you solved each problem without paper and pencil.

  1. 89,300 − 102 =
  2. 77,900 + 1100 =
  3. 65,800 − 5099 =

Use paper and pencil to solve Problems D–F. Estimate to make sure your answers make sense. Show your estimation strategy for Problem F.