Question

if a pressure of 10 psi on a volume of 5"^3 is reduced to 2 psi, by what factor does the pressure change?

Answer 1

is that "pressure change" or "volume change"?
if pressure change, new pressure is one-fifth of the original pressure, or
2/10 = 1/5

if volume change,, at a constant temperature, the new volume becomes five times the original, or
5*5 = 25 cubic inches
..since pressure is inversely proportional to volume

so there,, :)