Karina and Perry are cleaning up litter in the park for community service hours. Karina and Perry both claim they have covered the greatest area. Who is correct? Justify your answer using mathematical reasoning.
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Answer:
Perry is correct, she covered the greatest area = 18 square units.
Step-by-step explanation:
Looking at the attached diagram, the shapes are rectangular and they are on grid or graph
Note that on a graph:
1 square box = 1 unit
Area of rectangle = Length × Width
For Karina
The Width = 3 units
The length = 4 units
The area which Karina covered = 3 units × 5 units
= 15 square units
For Perry
The Width = 9 units
The length = 2 units
The area perry covered = 9 units × 2 units
= 18 square units
Therefore, Perry is correct, she covered the greatest area = 18 square units.