Two congruent squares share a vertex. What fraction is yellow?

Scroll down for a solution to this problem.

## Solution

The yellow fraction is 1/3.

If we assume that intersection H is midway the upper square sides also, we can see from the above graph that this is a valid solution. Since there is only one solution, this must be it.

Now we easily see that the yellow overlap kite is half a square, so it is 1/3 of the total area.