Answer
475 mmHg
Work Step by Step
$V_{1}$ = 10.0 L
$p_{1}$ = 655 mmHg
$V_{2}$ = 13800 mL = 13.8 L
According to Boyle's law, $p_{1}V_{1} = p_{2}V_{2}$
Or $p_{2}$ = $\frac{p_{1}V_{1}}{V_{2}}$ = $\frac{655 mmHg\times10.0 L}{13.8 L}$ = 475 mmHg.