Basic Mathemathics Practice Problems - Basic Mathematics for Water and Wastewater Operators - page 263

15. A rectangular trench is 700 ft long, 6.5 ft wide, and 3.5 ft deep. What is the
volume of the trench in cubic feet?
16. The diameter of a tank is 90 ft. If the water depth in the tank is 25 ft, what
is the volume of water in the tank in gallons?
17. A tank is 80 ft long, 20 ft wide, and 16 ft deep. What is the volume of the
tank in cubic feet?
18. How many gallons of water will it take to fill an 8-in.-diameter pipe that is
4000 ft in length?
19. A trench is 400 yd long, 3 ft wide, and 3 ft deep. What is the volume of the
trench in cubic feet?
20. A trench is to be excavated. If the trench is 3 ft wide, 4 ft deep, and 1200 ft
long, what is the volume of the trench in cubic yards?
21. A tank is 30 ft wide and 80 ft long. If the tank contains water to a depth of
12 ft, how many gallons of water are in the tank?
22. What is the volume of water, in gallons, contained in a 3000-ft section of
channel if the channel is 8 ft wide and the water depth is 3.5 ft?
23. A tank has a diameter of 70 ft and a depth of 19 ft. What is the volume of
water in the tank in gallons?
24. If a tank is 25 ft in diameter and 30 ft deep, how many gallons of water will
it hold?
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25. A channel 44 in. wide has water flowing to a depth of 2.4 ft. If the veloc-
ity of the water is 2.5 fps, what is the flow in the channel in cubic feet per
m inute?
26. A tank is 20 ft long and 12 ft wide. With the discharge valve closed, the
influent to the tank causes the water level to rise 0.8 feet in 1 minute. What
is the flow to the tank in gallons per minute?