A triangle is cut from the corner of a rectangle. The resulting pentagon has sides of length 8, 10, 13, 15 and 20 units, though not necessarily in that order. What is the area of the pentagon?
Select one option, then click Submit.
252.5
260
270
275.5
282.5
Select an option, then submit.
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Senior Mathematical Challenge 2007 (2007)
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