Challenge question #35 (31/10/2016)
Junior Question
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How many triangles are contained in this figure?
Senior Question
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Suppose a group of numbers are written in a grid of rows and columns.
Amanda finds the maximum value of each row, and then finds the minimum of these values, which she calls $A$.
Bill finds the minimum value of each column, and then finds the maximum of these values, which he calls $B$.
Show that $A$ must be greater than or equal to $B$.