Core TradesQuestion 87 of 700
CALCULATION: A 3-inch horizontal drain pipe is installed at the common 1/4 inch per foot slope. Over a 40-foot run, how much does the invert drop from start to end?
a.10 inches
b.5 inches
c.20 inches
d.40 inches
Explanation
Drop = slope x length = 0.25 inch per foot x 40 feet = 10 inches. Answer 5 uses 1/8 inch per foot; 20 uses 1/2 inch per foot; 40 uses 1 inch per foot.
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