[tex]\bf \begin{array}{ccll}
samples&lbs\\
\text{\textemdash\textemdash\textemdash}&\text{\textemdash\textemdash\textemdash}\\
10&0.1\\
1000&x
\end{array}\implies \cfrac{10}{1000}=\cfrac{0.1}{x}\implies x=\cfrac{1000\cdot 0.1}{10}[/tex]
you could also look at it this way, 1000 samples is really 10 * 100, or 100 times 10, if 10 weight 0.1, then 100 times that will just be 100 * 0.1.