Thread: Rates of change

A trough is 12 feet long and 3 feet across the top (see figure). Its ends are isosceles triangles with altitudes of 3 feet.

(a) If water is being pumped into the trough at 2 cubic feet per minute, how fast is the water level rising when h is 1.3 foot deep?

_________ ft/min
(b) If the water is rising at a rate of inch per minute when h = 2.1, determine the rate at which water is being pumped into the trough.
_________ ft^3/min

Originally Posted by tradar

A trough is 12 feet long and 3 feet across the top (see figure). Its ends are isosceles triangles with altitudes of 3 feet.

(a) If water is being pumped into the trough at 2 cubic feet per minute, how fast is the water level rising when h is 1.3 foot deep?

_________ ft/min
(b) If the water is rising at a rate of inch per minute when h = 2.1, determine the rate at which water is being pumped into the trough.
_________ ft^3/min

Have a look here: http://www.mathhelpforum.com/math-he...-calculus.html

That helped for the first part...THANKS!

how do I relate that to the second part?

Originally Posted by tradar

That helped for the first part...THANKS!

how do I relate that to the second part?

I assume that you found out:



With question a) you plug in the values for and h and calculate

while with b) you plug in the values for and h and calculate