7. (10 points) Calculate $1000-257-84-43-16=$
【Analysis】According to the properties of subtraction, simplify the calculation as follows: $a-b-c=a-(b+c)$.
【Solution】Solution: $1000-257-84-43-16$
$$
\begin{array}{l}
=1000-(257+43)-(84+16) \\
=1000-300-100 \\
=700-100 \\
=600
\end{array}
$$

Therefore, the answer is: 600.