Lesson 5

Addition with Larger Numbers

Est. Class Sessions: 4

Daily Practice and Problems

Teacher Notes
X

TIMS Bit

Number not started by lightning:

166 − 85 = 81

85 + 85 = 170, so more than half the fires are started by lightning.

Y. Forest Fires

On an average day, there are 166 forest fires. Eighty-five of these fires are started by lightning. How many are started by something other than lightning?

Are more than half the fires started by lightning? Show or tell how you know.