Digital Assets Growth
1. **Stating the problem:**
We have a company's digital assets valued at 120 million in 2010, growing according to the unlimited growth model:
$$V = 120 e^{0.08t}$$
where $t$ is the number of years after 2010.
We need to find:
a) The value of the assets in 2020.
b) The time $t$ when the value reaches 500 million.
2. **Formula and explanation:**
The unlimited growth formula is:
$$V = V_0 e^{kt}$$
where $V_0$ is the initial value, $k$ is the growth rate, and $t$ is time.
3. **Part (a): Find value in 2020**
Since 2020 is 10 years after 2010, $t=10$.
Calculate:
$$V = 120 e^{0.08 \times 10} = 120 e^{0.8}$$
Using $e^{0.8} \approx 2.22554$,
$$V \approx 120 \times 2.22554 = 267.065$$
So, the value in 2020 is approximately 267.07 million.
4. **Part (b): Find $t$ when $V=500$**
Set:
$$500 = 120 e^{0.08t}$$
Divide both sides by 120:
$$\frac{500}{120} = e^{0.08t}$$
Simplify:
$$4.1667 = e^{0.08t}$$
Take natural logarithm on both sides:
$$\ln(4.1667) = 0.08t$$
Calculate $\ln(4.1667) \approx 1.4271$,
So:
$$t = \frac{1.4271}{0.08} = 17.83875$$
Therefore, the value reaches 500 million approximately 17.84 years after 2010, i.e., around mid-2027.
**Final answers:**
a) Value in 2020: approximately 267.07 million.
b) Time to reach 500 million: approximately 17.84 years after 2010.