A trough is 12 ft long and 2.9 ft across the
top. Its ends are isosceles triangles with an
altitude of 1.8 ft and vertex down.
Water is being pumped into the trough at
a rate of 1.4 ft^3/min.

How fast is the water level rising when the
water is 1.31 ft deep?
Answer in units of ft/min

Question

A trough is 12 ft long and 2.9 ft across the
top. Its ends are isosceles triangles with an
altitude of 1.8 ft and vertex down.
Water is being pumped into the trough at
a rate of 1.4 ft^3/min.

How fast is the water level rising when the
water is 1.31 ft deep?
Answer in units of ft/min

phi · Answer

The volume of the trough is area of the base (the triangle) times its length.

The first thing you need to do is find the area of the base, as a function of "h", the water level.

phi · Answer

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