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Solutions to I-Practice Math #3

15.  A drum contains 55 gallons of a solution with a specific gravity of 1.25.  The empty drum weighs 25 pounds.  The weight of the filled drum is _____ pounds.

55 gal x 8.34 lbs/gal x 1.25 = 573.4 lbs

573.4 lbs + 25 lbs = 598.4 lbs

16.  55 gallons of a 0.15% chemical solution contains _____ pound(s) of dry chemical.

55 gal x 8.34 lbs/gal x 0.15 ¸ 100 = 0.688 lbs of dry chemical

17.  A feed pump lowers a 15 foot diameter chemical solution tank containing a 4.5% solution 8 inches in 20 minutes.  The pump delivers ______ pounds/day of solution.

15 ft x 15 ft x 0.785 x 8 in ¸12 in/ft x 7.48 gal/ft³ = 881 gal of solution

881 gal ¸ 20 min = 44 gpm of solution

44 gpm x 1440 min/day = 63,415 gpd of solution

63,415 gpd x 8.34 lbs/gal = 528, 885 lbs/day of solution

18.   A feed pump that lowers a 15 foot diameter chemical solution tank 8 inches in 20 minutes delivers _______ gpd.

15 ft x 15 ft x 0.785 x 8 in ¸12 in/ft x 7.48 gal/ft³ = 881 gal of solution

881 gal ¸ 20 min = 44 gpm of solution

44 gpm x 1440 min/day = 63,415 gpd of solution

19.   A pump that lowers a 15 foot diameter chemical solution tank 8 inches in 20 minutes delivers _______ gpm.

15 ft x 15 ft x 0.785 x 8 in ¸12 in/ft x 7.48 gal/ft³ = 881 gal of solution

881 gal ¸ 20 min = 44 gpm of solution

20.   A slurry was prepared by adding two 40 pound bags of a chemical to a 55 gallon drum and adding enough water to fill the drum.  The slurry contains _____ pound(s) of chemical.

40 lbs x 2 = 80 lbs of chemical

21.  If a bag of polymer weighs 60 pounds and contains 4.5% of a certain chemical by weight, the weight of that chemical is ______ pounds.

60 lbs x 4.5% ¸ 100% = 2.7 lbs of chemical

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