# Question #c895d

Mar 31, 2017

I got $7634$

#### Explanation:

Have a look: So at $t = 10$ we get:
$y \left(10\right) = 10 , 000 {e}^{- 0.027 \cdot 10} = 7633.79 \approx 7634$

Mar 31, 2017

7627

#### Explanation:

Treat this the same way you do for compound interest. Only it is minus the percentage rather than plus

So $\text{ "P(1+x)^n" becomes } P {\left(1 - x\right)}^{n}$

Thus we have:

set $1 - x \text{ as } X$ giving

$10000 {\left(X\right)}^{6} = 8500$

So we need to determine $X$

${\left(X\right)}^{6} = \frac{8500}{10000} = 0.85$

Taking logs:$\text{ }$ I choose the logs of $\text{ } \ln \to {\log}_{e}$

$6 \ln \left(X\right) = \ln \left(0.85\right)$

$\ln \left(X\right) = \ln \frac{0.85}{6}$

$X = {\ln}^{- 1} \left(\ln \frac{0.85}{6}\right) = 0.97327 \ldots$
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
So for 10 days we have

$10000 {\left(0.97327 \ldots\right)}^{10} = 7627.195 \ldots$

Call this 7627

The 0.195.. means that those people are still alive but 'on the road' to death.