3 3 8 8 - Solution

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March 2001

3 3 8 8 - Solution

The trick to this problem was finding a way to make the most of the two 3's and two 8's that you could use. The answer was:

24 =
  \[  8\over \displaystyle 3- { 8 \over \displaystyle 3}  \]    
To see how this works, start by writing the left hand side as:
  \[  {8 \over 1}\over \displaystyle 3- { 8 \over \displaystyle 3}  \]    
When you multiply this out it becomes clear that it is correct.
  \[  {{8\over 1} \over \displaystyle {{9- 8} \over \displaystyle 3}} = {{8 \times 3} \over {(9-8) \times 1}} = {24 \over 1} = 24  \]    
Clever isn't it!

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