The doors of perception

Two line segments and three rectangles, two of which have a given area. What is the yellow area?

Scroll down for a solution to this problem.


The yellow area is 3.

The crux is noting that the two triangles below the rectangles are similar, as are the ones above. This gives rise to two equations: b/c=d/e and a/d=c/f. This can be combined to abef=c2d2. In other words AC=B2. In this case C=36/12=3.

Note that the equations also give a/b=e/f. In other words, the blue and yellow rectangle are similar.


Just a psychedelic experience
with a good friend mescaline
to get perception and acknowledging
and better understanding
for mysteries and reasoning
in higher and higher awareness
Aldous saw Adam in the morning
Miss mescaline at work was inhibiting
Words of poetry evocating


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