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Direct answer
A drain falls 3/4 inch per foot over an 8-foot run. What is the total fall is a TradeCert Prep study concept connected to Plumbing License Practice Test prep, not a copied official exam item. Multiply 0.75 inch per foot by 8 feet to obtain 6 inches of fall. Always verify licensing, certification, and testing rules with the current official candidate bulletin, state manual, code book, or testing provider before relying on a detail for compliance.
How to use this answer
Read the answer once, then prove it by choosing an answer in a practice question before looking at the explanation. If the miss repeats, tag the domain as Math and drill a smaller set before returning to mixed practice.
Prep path
Plumbing License Study Guide
Independent journeyman and master plumber license study guide for state-specific code review, drainage, venting, traps, water supply, fixture units, and trade math.
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Public Plumbing License Practice Test sample questions with explanations.
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