## Elementary Technical Mathematics

You need $3$ mL.
RECALL: $P=BR$ where $B$=base, $P$=part, and $R$= rate or percent The given problem has: $B=2000$ mL $R=0.15\%$ Solve for $P$ using the formula above to obtain: $P=BR \\P=0.15\% \times 2000 \\P=0.0015 \times 2000 \\P=3 \text{ mL}$ Thus, you need $3$ mL.