# In what year does the population reach $75\%$ capacity?

A certain population of giraffes follows a logistic growth model. In the year 2000, the population was at $10\%$ of its capacity. In 2010, the population was $20\%$ of capacity. In what year does the population reach $75\%$ capacity?

How would I set up a differential equation? Thanks.

If you want an exact equation, use $p(t)=10\%·e^{c·t}$, so that $e^{10c}=2$ and $e^{cT}=7.5$ for the exact time $T$ (in years).