Lesson 4

Paper-and-Pencil Multiplication

Est. Class Sessions: 2

Daily Practice and Problems

Teacher Notes
X

TIMS Challenge

DPP Challange N can be used as a Problem of the Week.

  2. Seven billion, eighty-five million, two hundred ninety-eight thousand.
  3. Answers will vary. Possible response: First I identified the place value. For D it's hundred thousands, for F it's thousands. Then I regrouped to add or subtract.
  4. About 70 billion mosquitos. Possible response: I multiplied 7 billion by 10.

N. Mosquitos

Mosquito populations are often affected by the amounts of rainfall and changes in weather patterns. At the beginning of the season, the Mosquito Control Center sampled the population and estimated the number of mosquitos in the area they study to be 7,085,298,000. The table shows the increases and decreases that occurred during the season.

  1. Complete the table.
  2. Write the mosquito population at the beginning of the study in words.
  3. Explain how you solved Question 1D and Question 1F.
  4. In another district, the mosquito population is about ten times as large at the beginning of the season. About how many mosquitos are in this area? Show or tell how you know.