Question

Carry out the following operations as if it were a calculation of real experimental results. Express the answer with the correct number of significant figures.

 

(3.26 × 10⁻³ mg ) − (7.88 × 10⁻⁵ mg )

Answer 1

$(326 \times 10^{-5} \;mg) -(7.88 \times 10^{-5} \;mg) \\ = 318.12 \times 10^{-5} \;mg \\ = 3.18 \times 10^{-3} \;mg$