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Scratch file designed by Linda Fahlberg-Stojanovska.

Activity Notes

We have 4 balls - 2 Reds and 2 Greens. We drop them randomly into 2 boxes.
Are the colors mixed or separate?

These two events are mutually exclusive and complete.

(a) Both boxes will have will have 1R & 1G.
   We call this event: MIXED colors.

(b) One box 2G, other box 2R.
   We call this event: SEPARATE colors.

Guided Activity

Do the experiment 200-1000 times.

  • What is the percent of mixed?
  • What is the percent of separate?

Now for some dreaded theory ...
Number the balls:

  • How many different ways can the balls drop into the boxes?
  • How many times does mixed occur?
  • Does your theory match your experiment?

"Mutually exclusive" meaning both events cannot happen at same time and "complete" meaning no other event can occur.

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Page last modified on January 27, 2009, at 10:19 AM