Simple equilibrium in monopoly question
The monopolist solves,

$\max \pi=R(Q)-C(Q)=P(Q)Q-C(Q)$

The general solution is (if the problem is globally concave)

$MR(Q^*)=P'(Q^*)Q^*+P(Q^*)=C'(Q^*)$. 

Since $P'(Q)&lt;0$, notice that $MR(Q)&lt;P(Q)$ and, therefore, $Q^*&lt;Q^{C}$. 

In this example, we have $P(Q)=3-\frac{Q}{16000}$ and $C(Q)=Q$. Hence, 

$MR(Q)=-\frac{1}{160000}Q+(3-\frac{Q}{16000})=1=MC(Q)$.

Rewritting, we get
$3-\frac{Q}{8000}=1$ or $Q=16000$. To compute the price simply substitute in the demand function and get $P(16000)=3-1=2&gt;1$.