Triangle in a Quadrilateral
Quadrilateral ABCD is a rectangle with length to width in the ratio of 3 : 2. AN and BM are bisectors of angle A and angle B, respectively. What is the ratio of the area of the shaded region to the area of ABCD? Explain your solution.

Extensions 
How does your answer change if quadrilateral ABCD is a parallelogram?
(Source: Mathematics Teaching in the Middle School, Feb 1998)
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