Blush!...You're quite right! Math errors are indeed humbling.
Also, I chose the wrong celestial body. The moon instead of Mars.
Mars surface gravitational attraction rate is...ROUGHLY...4 meters per second squared,
give or take a fraction of a meter thereof.
So! [245-260m/s] / [9.8m/s^2 - 4.0m/s^2] = [ROUGHLY] 45 seconds.
Hmmmm...45 seconds, give or take a second or two.
What can you do in 45 seconds in Martian gravitational conditions, mate?
Don't answer that, Nick, if you're salacious. Wink wink!
NOW it's you're turn to blush, Nick.
Jacob