WTO Math 3

Question 1

A filter has a surface area of 400 ft² and a flow rate of 1,600 gpm. What is the filtration rate in gpm/ft²?

Accepted Answer

4 gpm/ft²

Answer

5 gpm/ft²

Answer

3 gpm/ft²

Answer

6 gpm/ft²

Question 2

A settling basin is 60 ft long, 20 ft wide, and 10 ft deep. What is its volume in gallons?

Accepted Answer

89,760 gal

Answer

79,680 gal

Answer

99,840 gal

Answer

69,600 gal

Question 3

The plant flow is 4.2 MGD. Express this flow in gallons per minute (gpm).

Accepted Answer

2,917 gpm

Answer

3,150 gpm

Answer

2,500 gpm

Answer

3,400 gpm

Question 4

A 10% sodium hypochlorite solution is needed to deliver 6 lbs of chlorine. How many gallons of solution are required?

Accepted Answer

7.19 gal

Answer

8.34 gal

Answer

6.00 gal

Answer

9.50 gal

Question 5

A pump runs 14 hours per day and delivers 350 gpm. How many million gallons does it deliver in 30 days?

Accepted Answer

8.82 MGD

Answer

8.40 MGD

Answer

9.24 MGD

Answer

7.98 MGD

Question 6

A water sample has a turbidity of 0.8 NTU before filtration and 0.04 NTU after. What is the percent removal?

Accepted Answer

95%

Answer

90%

Answer

85%

Answer

80%

Question 7

The detention time in a contact chamber is required to be at least 30 minutes at a flow of 5 MGD. What minimum volume (in gallons) is needed?

Accepted Answer

104,167 gal

Answer

150,000 gal

Answer

83,333 gal

Answer

208,333 gal