Cut the knot: learn to enjoy mathematics
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Plus or Minus

In the simple game below you start with a sequence of numbers. Taking turns you and your computer place either plus or minus sign between any two successive numbers. When all empty spaces have been filled, the arithmetic expression is evaluated. You win if the result is odd. If the result is even, your computer is the winner.

There is a button "+" at the bottom of the applet. Pressing it will toggle "+" and "-". This is to tell you what sign will be inserted upon your click. If the Random checkbox is checked, the applet selects randomly the length of the sequence. Otherwise, it's up to you: try playing short (even very short) sequences first.

<hr> <h3> This applet requires Sun's Java VM 2 which your browser may perceive as a popup. Which it is not. If you want to see the applet work, visit Sun's website at, download and install Java VM and enjoy the applet. </h3> <hr>


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