2014-07-14

171. Fraction redistribution

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There is a number such that, when it is subtracted from the numerator of the fraction \(\frac{5323}{7577}\) and added to the denominator, the fraction reduces to \(\frac{17}{83}\).  Determine the number.

2014-07-01

170. Self-intersecting polygon

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Determine ∠A + ∠B + ∠C – ∠D + ∠E – ∠F + ∠G + ∠H.

2014-06-25

169. Balls and boxes

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There are 4 balls, numbered 1 to 4, and 4 boxes, numbered 1 to 4.  Determine how many ways one ball can be put into each box so that the number of the ball and the number of the box are different.