Math Is Fun Forum

While sitting around waiting for interior decorators to finish up in the scroll repository, a bunch of bored and mischievous workers decided that they'd build a catapult. When they finally finished, it was able to shoot a projectile straight up into the air. So. in a move which they later regretted, they decided to launch one of the pyramid blocks, which had a density of 2400 kilograms per cubic meter.

When the block crashed back into the catapult, smashing it to pieces, it was determined to have a velocity of 20 meters per second. Assuming that gravity is exactly 9.90 meters per second squared, the block hit the catapult at the same elevation as it was launched from the catapult, and there was, miraculously, no air resistance acting on the block, how high, in centimeters, did the block fly above the catapult? Please round to the nearest centimeter.