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Decompose shapes to find area

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Decompose shapes to find area
Exercise Name: Decompose shapes to find area
Math Missions: 3rd grade (U.S.) Math Mission, 6th grade (U.S.) Math Mission
Types of Problems: 1

The Decompose shapes to find area exercise is under the 3rd grade (U.S.) Math Mission and 6th grade (U.S.) Math Mission. This exercise explores helps to understand how to find area by breaking down complicated shapes into smaller and more manageable shapes.

Types of Problems

There is one type of problem in this exercise:

  1. Find the area of the entire figure: This problem has a shape composed of many rectangles and the user is supposed to find and answer the total area. Most of the problems involve adding smaller rectangles, but some can be done by taking the large rectangle and subtracting.

    Find the area of the entire figure


This exercise is easy to get accuracy badges because of the actual multiplications are only single digit multiplies. The adding can involve carrying. The speed badges are medium difficulty but are very reasonable once one is able to get into a good habit of recognizing the rectangles that are being added or subtracted.

  1. If user is going for speed badges, it might be wise to keep a calculator handy for some of the addition that needs carrying.
  2. The labels on the side can be used to make things easy. Research indicates that there is no problem that forces the need to subtract numbers before multiplying.

Real-life Applications

  1. The ancient Egyptians from over 4000 years ago were very good at shapes and geometry. Every time the Nile burst its banks and flooded the planes, they had to use geometry to measure their gardens and fields all over again.
  2. Area and perimeter are used in many jobs for architecture and interior design.

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