Another way to kind of just talk about this is to get the present value of 110 a year from now, we discount the value by a discount rate.

These are 30 percent off.

Then to discount money in the future to the present, we divide it by 1 plus the discount rate so this is a 5 discount rate.

Do you have a student fare?

Well, that was x.

60 off.

Are there special evening rates?

So x minus twenty five percent x is equal to the sale price.

Well the antiderivative of y squared and you have to divide by 3, so it's y cubed over 6.

We could have said Let y equal the discount

The probability of reaching S prime given that we started state S and apply action A.

Are there any discount tickets for me?

35 divided by and it's 2 years out, so we discount by our discount rate twice so it's divided by 1.05 squared.

If there's a 10 dollar product, we can put that 10 dollar product in here for x, and then we would say 0.30 times 10.

And we didn't have to use these words and these letters.

A mechanism allowing survival

But what a virus does is it hijacks this process here.

In this example that I did in the previous video, it was the pre tax return on asset.

Now this is really interesting, now we have a general way of calculating a discount for any given percentage off and any given product x.

Then we get the Q value of 100 minus the Q value of zero, and the discount rate is 90.

And this one that was in Kenya, they went around and distributed to people vouchers, discount vouchers.

So you could view this as being equivalent to So we're going to do our multiplication before we do any addition or subtraction, and we're going to do our division before doing any addition or subtraction.

So this is 8t squared plus I'm just dividing both sides of this equation by 2.

Discount rate

Now what can we do ?

It's almost like they get heavy. They get massive.

when the sale has a certain percentage ?

You would multiply thirty percent times the twenty dollars. so you would say your discount your discount is equal to, you could write is as 30 times 20.

Roughly, what this operator does is it halves a number.

Draw edges along the grid lines which divide the rectangle under certain rules

So we take 110, and we're going to use the two year rate, and discount twice.

And if we look at the formula we figured out, we would say, well, that is just equal to 1 2 to the n plus 1, minus 1, over 1 2 minus one.

And this risk free is the big assumption.

Using triple quotes, we can define one string spread over multiple lines.

Oftentimes you want to discount a payment two years out by a higher value than something that's only one year out.

To compound the amount of money we invest we multiply the amount we invest times 1 plus the yield.

So we're subtracting 40, and we're subtracting 2.

They're SG amp A, let's say it's another 500,000 every year.

So 2009 money, that's worth 1.

I'll say p, just so it makes sense, p is equal to the percentage off.

Here we grew the money by you could say our yield, a 5 yield, or our interest.

And we can work out from this what the number for the parent ought to be.

Now, this numerator up here, we can factor it.

And it just depended on how the mathematics work out.

And then how much are just those cupcakes costing me?