Lemmas

Calculus Challenge #9 Solution Houdini?s Escape Houdini plans to have his feet shackled on the top of a concrete block which was placed on the bottom of a giant flask. The cross-sectional radius of the flask, measured in feet, is given as a () 10 function of the height y from the ground by the formula ry = , with the bottom of the flask y at y = 1 foot. The flask is to be filled with water at a constant rate of 22pcubic feet per minute. Houdini?s job is to escape the shackles before he drowns! Houdini knows that he can escape the shackles in exactly 10 minutes. For dramatic effect, he wants to escape at the moment the water level reaches the top of his head. Houdini is 6 feet tall.