Help! Chemistry math problem.?

Question

A balloon is up at an altitude of 6000 ft where the pressure is 605 torr and temperature is 15 degrees Celcius. At sea level, here we're at 25 degrees Celcius with a pressure of 720 torr, what will be the change in volume?

i don't really understand how to get the volume. i have altitudes, but its all really confusing to me.

Answer 1

Combined gas law:

P1 x V1 / T1 = P2 x V2 / T2

Remember to add 273 to Celsius to convert to Kelvin before working the problem.