This Instructional Activity is a part of the Lesson 27, Unit 6, Grade 7. A square pipe (a rectangular prism-shaped pipe) with given inside dimensions has water flowing through it at a flow speed of 3. The water flows into a pool in the shape of a right triangular prism, with a base in the shape of a right isosceles triangle and with legs that are each feet in length. How long will it take for the water to reach a depth of 4 feet? This problem is slightly different than the previous example. In this example, we are given a flow speed (also known as linear flow speed) instead of a flow rate.