Using A Grid To Calculate The Area Of An Irregular Figure

Estimate the Surface Area of Lake Chad

Work Time

Estimate the Surface Area of Lake Chad

One method geographers use to find the area of an irregularly shaped lake is to use a grid.

The scale of the grid shown on this image of Lake Chad is each small square represents a 10 mile by 10 mile area.

  • Why do you think the grid is slanted?
  • Make an estimate of the area of the lake using the grid.

Hint:

  • What is the area of one square?
  • If a square completely overlaps the lake, what do you know?
  • If a square only partially overlaps the lake, what can you do?
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