Estimable reader: A dialogue appended to problem 42 highlights an unsettling outcome of a limited (and limiting) approach to mathematics education.

2015-05-05

242. Overlapping rectangles

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In the diagram, A and B are two overlapping rectangles.  The sum of the areas of A and B is 123 cm².  The fraction of A that overlaps is ⁴⁄9, and the fraction of B that overlaps is ⁶⁄7.  Determine the area of the overlap.

2015-05-04

241. Triangular table



Numbers are arranged according to a particular rule, as shown.

⒜  Determine the number at the left end of Row 7.
⒝  Determine in which row the number 100 is located.
⒞* Determine the sum of the numbers in Row 10.

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2015-04-30

240. Triple triangles

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In the diagram are three identical 30-60-90 triangles.  Determine the ratio AP : PB.