time until gas is depleted cylinder

If one has a $10$ liter (water volume) tank of gas at $15$ Mpa, then how long until gas is depleted if gas is exiting the cylinder at a rate of $15$ liters per minute?

ATM i have used ideal gas law, $PV=nRT$ and derive at constant temp to get:

$P(1) \times V(1) = P(2) \times V(2)$ where $P(1)$ is pressure of compressed gas in cylinder ($15$ psi), $V(1)$ is internal volume of cylinder ($10$ litres), $P(2)$ is atmospheric pressure ($14.7$ psi) and $V(2)$ is volume of gas at pressure. This gives me $1360$ litres of gas inside the cylinder.

Is it simply $\dfrac{1360}{15}$ to get the time gas would last in minutes before gas in tank equals atmospheric pressure?

Applying $P_1V_1 = P_2V_2 => 2175.565*10 = 14.7*V_2 => V_2 = 1480$
Thus the time it takes for the cylinder to be depleted$= 1480/15 = 98.666$ minutes