Complete the diagrams. Use each diagram to find the value of .
A
Diagram, rectangle partitioned vertically and horizontally into 6 rectangles. Top left rectangle, vertical side, 30, horizontal side, two hundred. Top middle rectangle, horizontal side, fifty. Top right rectangle, horizontal side, 3. Bottom 3 rectangles, vertical side, 1.
B
How are the strategies alike? How are they different?
The recommended side lengths for a birdhouse for a yellow-bellied sapsucker are 13 centimeters by 13 centimeters for the floor and a height of from 31 centimeters to 38 centimeters. What are the least and greatest volumes for this birdhouse? Explain or show your reasoning.
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Problem 15
Exploration
Student Task Statement
Jada remembers that the partial-products algorithm can go from left to right or from right to left. She wonders if the standard algorithm also can go in either direction.
Calculate , using partial products right to left and left to right.
Calculate , with the standard algorithm. What happens if you try to make the calculation from left to right?
Problem 16
Exploration
Student Task Statement
Clare has a strategy for multiplying a number by 99. To find , she calculates and then subtracts .
Use Clare's strategy to calculate .
Use the standard algorithm to calculate .
Which strategy do you prefer? Explain your reasoning.