Silver Dollars and Babies: Discussing Probability

Results after coin tossing game 1

"Life is a school of probability."

-Walter Bagehot

I don't believe that we have ever really talked much about probability before, but we had fun discussing the concept the other day while playing a classic coin toss.

Hunter loves coin tossing (he's a little bit competitive) and will often initiate a game randomly, usually asking me to guess which side it will be.

After being prompted for my guess several dozen times, I told him that my guess would always be heads. We then decided to start recording how many we each got right. Over the course of many throws, this illustrated the idea that they would be pretty much even, if though it wasn't a perfect pattern of heads; tails; heads; tails... etc.

He had fun watching the game progress on paper. Sometimes we would get tails after tails after tails, sometimes the other way around, but one person would always end up catching up, or switching between who was in the lead.

We discussed why this was, and the concept of probability.

Seeing it written down on paper really made it stick about the concept of chance, and that the chances were even, even if the pattern wasn't exactly even.

We discussed that because there were two choices, and it was pure chance which side it landed on, about half of the throws would be heads, and half would be tails, or in other words, 50 out of every 100.

We said this many different ways throughout the process of the game:

There is a 50% chance that it will be one or the other.

It is a 50:50 chance it will be one or the other.

There is a 1 in 2 chance it will be one or the other.

etc., etc.

We talked about how there was a 1 in 2 chance of a baby being a boy or a girl, but just like with coin tossing, it is not always an even pattern. Sometimes you get boy, girl, boy, girl, and sometimes you get several of the same in a row, like us having two boys!

We talked about how if you had something that had more than two side, the chances would be different, like if you had a die. But we will come back to that later.

Just a lot of fun math talk, while sitting on the couch and playing a silly little game. I have been inspired to make the language of math a bigger part of our vocabulary, and it has been fun seeing the many places it has taken us - if only I wrote about all the many discussions we have had! Truly, mathematics is everywhere, we just have to notice it.

First game results - Hunter, 48: Mom, 52

Second game results - Hunter, 56: Mom, 44

"Let my sentence come forth from thy presence; let thine eyes behold the things that are equal." 

Psalm 17:2

Hunter is 5 years, 11 months old