Help me figure out the pressure of the gas!!?

Question

The pressure of the gas in the 1.00 L bulb is 649 mm Hg and that of the gas is the 0.500 L bulb is 455 mm Hg
What is the pressure (atm) of the system when both valves are opened, assuming the temperature remains constant ?
(neglect the volume of the capillary tube connecting the bulbs)

Answer 1

the number of moles in the 1 L bulb is using pV=nRT

n1 = pV /nR = 649 *1 /RT = 649/RT

for the 0.5 L we obtain n2 = 445 * 0.5/RT= 222.5/RT

n1+n2 = 871/RT which is put in a total volume of 1.5 l

So, the pression is 871/1.5 = 581.2 mm Hg

Note that with my answer, you need not to know neiter the temperature nor to convert the pression in mmHg in pascals or atmospheres