Question 15
A container has a $1 \times 1$ square bottom, a $3 \times 3$ open square top, and four congruent trapezoidal sides, as shown. Starting when the container is empty, a hose that runs water at a constant rate takes $35$ minutes to fill the container up to the midline of the trapezoids.
How many more minutes will it take to fill the remainder of the container?
How many more minutes will it take to fill the remainder of the container?