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Enclosed area (Posted on 2005-02-01) Difficulty: 1 of 5
Imagine a square ABCD with a diagonal BD. Now draw a line EF parallel to BD, such that E lies on BC and F lies on CD. Also length of EF = length of AB. Now Colour the space enclosed by BDFE. Of the square ABCD, what percentage of area is coloured ?

See The Solution Submitted by Syzygy    
Rating: 2.1667 (6 votes)

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It is too easy.... | Comment 3 of 6 |

Four triangles ECF, with their right angles (corner C) placed together would form a square of side length EF (which is equal to AB).  Therefore triangle ECF occupies one quarter of the area of the square ABCD.

As ECF is half of BCD which is half of ABCD, then BEFD is a quarter of area ABCD too.

Sorry, 25% (Never say things are too easy and then fail to answer the question - makes you look like an idiot, that's what it does.)

Edited on February 1, 2005, 3:10 pm

Edited on February 1, 2005, 3:14 pm
  Posted by Fletch on 2005-02-01 14:59:09

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