Yellow
Green
Blue
Red
Magenta
Remove
- To use whole numbers to solve 21 ÷ 0.07, multiply both the dividend and the divisor by 10, 100, and 1000.
- (21 10) ÷ (0.07 10) =
- (21 100) ÷ (0.07 100) =
- (21 1000) ÷ (0.07 1000) =
- What did you notice? Which problem was easiest to solve?
- Is (21 100) ÷ (0.07 100) = 21 ÷ 0.07 a true statement? Why?
A Variety of Strategies
Mr. Moreno presented his students with this problem:
A gardener is planting seeds in rows in his garden. He plants one seed every 4 centimeters, or every 0.04 of a meter. One row is 2.4 meters long. How many seeds will he plant in one row?
Mr. Moreno asked his students to solve 2.4 ÷ 0.04.
Chris multiplied both the dividend and the divisor by 100 so he could divide whole numbers.
Julia thought about base-ten pieces:
2.4 = 100 hundredths + 100 hundredths + 40 hundredths
240 hundredths divided by 4 hundredths is 60.