Puzzles, Issue 01

These puzzles appeared in Issue 01 of the magazine.

#2 – Circles

2Source: MathsJam
Pictured are: a quarter circle with radius 2r, and two semi circles with radius r.
Prove that the pink area is equal to the green area.

#104 – Two Triangles

two_tri_whiteSource: MathsJam
In the diagram, the three sides of a triangle have been split into thirds, then the lines have been added.
What is the area of the smaller shaded triangle as a fraction of the area of the large triangle?

The answers to these puzzles are available here.

post

These puzzles appeared in Issue 01 of the magazine.

#2 – Circles

2Source: MathsJam
Pictured are: a quarter circle with radius 2r, and two semi circles with radius r.
Prove that the pink area is equal to the green area.

#104 – Two Triangles

two_tri_whiteSource: MathsJam
In the diagram, the three sides of a triangle have been split into thirds, then the lines have been added.
What is the area of the smaller shaded triangle as a fraction of the area of the large triangle?

The answers to these puzzles are available here.

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