A sizing problem leaves 24 psi available for friction loss. The measured developed length to the most remote fixture is 160 ft, and fittings are estimated to add 50 percent to that length. What is the allowable friction loss per 100 ft of pipe?

Explanation

Total equivalent length is 160 x 1.5 = 240 ft, so 24 psi / 240 ft x 100 = 10 psi per 100 ft. The 15 psi answer divides by the measured 160 ft and skips the fitting allowance. The 6.7 psi answer overstates the equivalent length, and 24 psi per 100 ft simply restates the total budget without dividing by length.