Using barometer to estimate height of mountain

At sea-level, the barometer which Pie is holding reads 760 mm of Hg.

When he is at the top of Mount Pie, the same barometer reads 230 mm of Hg.

Given take the density of mercury to be 13.6 g cm-3 and the density of air, 1.23 x 10-3 g cm-3.

Estimate the height of the mountain?

Solutions: 5860 m