## Elementary Technical Mathematics

$$2.13\times 10^{-3}.$$
We multiply and divide the two numbers as follows: $$\frac{(3500)(0.00164)}{2700}=\frac{(3.5\times 10^3)(1.64\times 10^{-3})}{2.7\times 10^3} \\ =2.1259 \times 10^{-3}=2.13\times 10^{-3}.$$