Teaching Elementary Probability

Date: 10/07/98 at 18:03:46
From: Daniel Talmage
Subject: Second grade math questions

A friend doesn't understand why her daughter's second grade math 
teacher is asking the following question:

If you toss a number cube twenty times, could it land on 6 twenty times?
Why or why not?

Date: 10/08/98 at 12:18:42
From: Doctor Peterson
Subject: Re: Second grade math questions

Hi, Daniel. 

It sounds as if the teacher is introducing basic ideas of probability, 
and wants to help the students distinguish between something that is 
unlikely and something that is impossible. 

If I rolled a die twenty times and always got a 6, you would probably 
wonder if I was cheating somehow. But there's no reason it couldn't 
happen, and in fact if you rolled enough times, you'd eventually get a 
string of twenty 6's. It would just take a very long time - probably. 

Later they'll learn how to calculate the probability of this 
happening, and still later they might learn how long it would take 
before they could expect it to happen.

- Doctor Peterson, The Math Forum
  http://mathforum.org/dr.math/