a)
b)
c) $$
\begin{align}
& 500 = N_{0}1.25^{1.25} \
& 500 = N(1.321714079) \
& \frac{500}{1.321714079} = 375.2966436
\end{align}
Function | Growth or decay | Initial | Rate |
---|---|---|---|
growth | 20 | 1.02 | |
decay | 1 | 0.8 | |
growth | 0.5 | 3 | |
decay | 600 | 5/8 |
- the growth in population of a small town since 1996 is given by the function
a) What is the initial population? Explain how you know.
The initial population is 1250 as it’s the value when n = 0
b) What is the growth rate? Explain how you know.
The growth rate is 1.03 or 3%. we can see that as it’s the b value in the growth function
c) Determine the population in the year 2007.
\begin{align}
& P = 1250(1.03)^{(2007-1996)} \
& P = 1730
\end{align}
\begin{align}
& 2000 = 1250(1.03)^n \
& \frac{2000}{1250} = 1.03^n \
& \frac{8}{5} = 1.03^n \
& \ln\left( \frac{8}{5} \right) = \left( \ln(1.03^n) = n * \ln(1.03) \right) \
& \frac{\ln\left( \frac{8}{5} \right)}{\ln(1.03)} = n \
& \boxed{n = 15.9}
\end{align}
d) In which month after it is purchased does the computer’s worth fall
below $900?
- . In 1990, a sum of $1000 is invested at a rate of 6% per year for 15 years.
a) What is the growth rate?
6%
b) What is the initial amount?
1000
c) How many growth periods are there?
15
d) Write an equation that models the growth of the investment, and use it
to determine the value of the investment after 15 years
- species of bacteria has a population of 500 at noon. It doubles every 10 h.
The function that models the growth of the population, P, at any hour, t, is $$
P(t) = 500\left( \frac{t}{2^{10}} \right)
\begin{align}
& 500\left( \frac{24}{2^{10}} \right) \
& \frac{375}{32} = 11
\end{align}