Big triangles first

Use the areas of the tangram pieces and the outline’s corners to choose a useful starting point.

Half the figure is two pieces

Two big triangles, one middle triangle, a square, a parallelogram and two small triangles.

All seven standard tangram pieces together have the area of sixteen small triangles. Each big triangle has the area of four small ones, so the two big triangles cover half the total area.

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Trying the big triangles first can help you organize a large part of the outline. It is a strategy, not a rule: a distinctive corner or notch may suggest another piece first.

In this square example, place the big triangles, then the middle triangle, the square and the parallelogram. The small triangles fill the remaining gaps.

Lesson help

The two big triangles cover half the total area. Try them as a starting point, and use distinctive corners and notches to guide your next placement.

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Half the figure is two pieces

All seven standard tangram pieces together have the area of sixteen small triangles. Each big triangle has the area of four small ones, so the two big triangles cover half the total area.

Trying the big triangles first can help you organize a large part of the outline. It is a strategy, not a rule: a distinctive corner or notch may suggest another piece first.

In this square example, place the big triangles, then the middle triangle, the square and the parallelogram. The small triangles fill the remaining gaps.

Two big triangles, one middle triangle, a square, a parallelogram and two small triangles.

The square, in order

Start with the square figure. The two big triangles fill the half of the square below one diagonal. They meet along a line from the center to a corner.

The middle triangle, the square and the parallelogram go in next and leave two triangular gaps.

The two small triangles fill those gaps, and the tray is full.

The empty tray
The two big triangles
Then the middle three
The two small ones finish it

Compare the areas

The same square is empty again.

Each big triangle has the area of four small triangles. All seven pieces together have the area of sixteen. What part of the square will the two big triangles cover without overlapping?

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What fraction of the square do the two big triangles cover together?

  1. A half (1/2)
  2. A quarter (1/4)
Show the answer

A half (1/2)

Together they cover half the square: 4 + 4 = 8 small-triangle units out of 16, so 8/16 = 1/2.

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