00:01
We're looking at roulette, there are 38 numbers and each one is equally spaced.
00:07
So we're saying that when you play roulette, there's an equal chance of each slot coming up.
00:12
So each slot has one in 38.
00:16
If you get a number and you win, you keep your dollar and you get an additional 35.
00:23
So the outcome here is you get an extra $35.
00:28
If you land on anything else, which would be 37 and 38, you lose your doll, so you get minus 1.
00:37
What's the expected value? so, from writing down the information, i've given myself a table.
00:43
I have the probability of my outcomes, and i have my outcomes.
00:50
The expected value, also called the mean, all you have to do to get it, so it's e, x, is you up your outcomes multiplied by their probabilities.
01:10
So you add these up and you get your expected value.
01:13
So that's what we're going to do...