Homework Day 1

Calculations

1. How many pounds are there in 64 ounces?
2. How many pounds are there in 176 ounces?
3. How many gallons are there in 384 fluid ounces?
4. How many gallons are there in 832 fluid ounces?
5. What is the length, in feet, of a pool 40 yards long?
6. What is the length, in feet, of a pool 50 yards long?
7. What is the length, in feet, of a pool 40 meters long?
8. What is the length, in feet, of a pool 50 meters long?
9. What is the surface area of a rectangular pool with a length of 20 yards and a width of 30 feet?
10. What is the surface area of a rectangular pool with a length of 10 meters and a width of 20 feet?
11. What is the surface area a circular spa with a 12 foot diameter?
12. What is the surface area a circular spa with a 9 foot diameter?
13. What is the volume of a rectangular pool with a length of 40 feet, a width of 20 feet, and a constant depth of 5 feet?
14. What is the volume of a rectangular pool with a length of 32 feet, a width of 16 feet, and a depth ranging from 3 feet in the shallow end to 6 feet in the deep end?
15. What is the volume of a rectangular pool with a length of 25 yards and a width of 45 feet? The pool has a swimming area that is 10 yards long that has a depth ranging from 3 feet to 5 feet, with a constant slope. The diving area has a length of 15 yards and a constant depth of 12 feet.
16. What is the volume of a rectangular pool with a length of 45 yards and a width of 65 feet? The pool has a swimming area that is 25 yards long that has a depth ranging from 4 feet to 6 feet, with a constant slope. The diving area has a length of 20 yards and a constant depth of 15 feet.
17. A pool 40 feet long and 20 feet wide lost 3 inches of water over the weekend. How many gallons of water must be replaced?
18. A pool 25 yards long and 25 meters feet wide uses two inches of water every backwash. How many gallons of water must be replaced?
19. A pool has a maximum bather load of 180 bathers. What should the storage capacity (in gallons) of the surge tank be?
20. A pool has a maximum bather load of 220 bathers. What should the storage capacity (in gallons) of the surge tank be?
21. What is the turnover rate of a 80,000 gallon pool with a flow rate of 167 gpm?
22. What is the turnover rate of a 150,000 gallon pool with a flow rate of 417 gpm?
23. What is the flow rate of a 50,000 gallon pool based on an 8 hour turnover rate?
24. What is the flow rate of a 120,000 gallon pool based on an 6 hour turnover rate?
25. What is the filter surface area needed for a high-rate sand filter that has a filtering rate of 15 gpm/sqft, if the flow rate is 313 gpm?
26. What is the filter surface area needed for a DE filter that has a filtering rate of 2.5 gpm/sqft, if the flow rate is 80 gpm?
27. What is the filter surface area needed for cartridge filter that has a filtering rate of .375 gpm/sqft, if the flow rate is 120 gpm?
28. How many BTU's are needed to raise the water temperature of 700 gallon spa from 82°to 104°?
29. How many BTU's are needed to raise the water temperature of 50,000 gallon pool from 60° to 84°?
30. If a 950 gallon spa has an average of 23 bathers per day, how many days before the water should be replaced?
31. If a 1350 gallon spa has an average of 63 bathers per day, how many days before the water should be replaced?
32. Calculate the Saturation Index for water that has a pH of 7.6, a temp- erature of 104°F, a calcium hardness of 400 ppm, a total alkalinity of 150 ppm and total dissolved solids of 800 ppm. Corrosive or Scale forming?
33. Calculate the Saturation Index for water that has a pH of 7.0, a calcium hardness of 100 ppm, total alkalinity of 50 ppm, a temperature of 84°F, and total dissolved solids of 1400ppm. Corrosive or Scale forming?
34. Calculate the Saturation Index for water that has a temperature of 66°F, and total dissolved solids of 200 ppm, a total alkalinity of 25 ppm, a pH of 7.0, and a calcium hardness of 50 ppm. Corrosive or Scale forming?

Answers

Ounces ÷ 16 = Pounds

1. 64 ÷ 16 = 4 Pounds

2. 176 ÷ 16 + 11 Pounds

Fluid ounces ÷ 128 = Gallons

3. 384 ÷ 128 = 3.0 Gallons

4. 832 ÷ 128 = 6.5 Gallons

Yards x 3 = Feet

5. 40 yards x 3 = 120 Feet

6. 50 yards x 3 = 150 Feet

Meters x 3.28 = Feet

7. 40 meters x 3.28 = 131 Feet

8. 50 meters x 3.28 = 164 Feet

Length X Width = Surface Area in Square Feet

9. ( 20 yards x 3= ) 60 feet x 30 feet = 1800 Square Feet

10. (10 meters x 3.28=) 33 feet x 20 feet = 660 Square Feet

3.14 X radius X radius = Surface Area in Square Feet

11. 3.14 X 6 X 6 = 113 Square feet

12. 3.14 X 4.5 X 4.5 = 64 Square Feet

Length X Width X Depth X 7.5 = Gallons

13. 40 Feet x 20 Feet x 5 Feet x 7.5 = 30,000 Gallons

Length X Width X Ave. depth (shallow + deep ÷ 2) X 7.5 = Gallons

14. 32 Feet x 16 Feet x 4.5 feet ( 3 + 6 = 9, 9÷2 = 4.5) x 7.5 = 17,280 Gallons

Swimming Area (SA)

Length X Width X Ave. depth (shallow + deep ÷ 2) X 7.5 = Gallons

30 Ft x 45 Feet x 4 Feet (3 + 5 = 8, 8 ÷ 2 = 4) x 7.5 Feet = 40,500 Gallons

Diving Area (DA)

Length X Width X Depth X 7.5 = Gallons

45 Ft x 45 Feet x 12 Feet x 7.5 = 182,250 Gallons

Total Pool Volume in Gallons

15. 40,500 Gallons (SA) + 182,250 Gallons (DA) = Total Pool 222,750 Gallons

Swimming Area (SA)

Length X Width X Ave. depth (shallow + deep ÷ 2) X 7.5 = Gallons

75 Ft x 65 Ft x 5 Ft (4 + 6 = 10, 10 ÷ 2 = 5) x 7.5 Feet = 182,813 Gallons

Diving Area (DA)

Length X Width X Depth X 7.5 = Gallons

60 Ft x 65 Feet x 15 Feet x 7.5 = 438,750 Gallons

Total Pool Volume in Gallons

16. 182,813 Gals (SA) + 438,750 Gals (DA) = Total Pool 621,563 Gallons

Length x Width x 0.0833 x 7.5 = Gallons per one inch

17. 40 Ft x 20 Ft x 0.0833 x 7.5 = 500 Gallons x 3 inches = 1500 Gallons

18. 75 Ft (25x3) x 82 (25x3.28) x 0.0833 x 7.5 = 3842 Gals x 2 ins = 7684 Gals

# of Bathers x 20 = Gallons

19. 180 x 20 = 3600 Gallons

20. 220 x 20 = 4400 Gallons

Volume ÷ Flow Rate ÷ 60 = Turnover Rate (in hours)

21. 80,000 ÷ 167 ÷ 60 = 8 Hours

22. 150,000 ÷ 417 ÷ 60 = 6 Hours

Volume ÷ Turnover Rate (in hrs) ÷ 60 = Flow Rate in Gallons per Minute

23. 50,000 ÷ 8 ÷ 60 = 104 Gallons per Minute GPM

24. 120,000 ÷ 6 ÷ 60 = 333 GPM

Flow Rate ÷ Filtering Rate (FMR) = Square Feet

25. 313 gpm ÷ 15 gpm/sqft = 21 Sqft.

26. 80 gpm ÷ 2.5 gpm/sqft = 32 Sqft.

27. 120 gpm ÷ .375 gpm/sqft = 320 Sqft.

Gallons x 8.33 x °change = BTU's

28. 700 gallons x 8.33 x 22 (104 - 82) = 128,282 BTU's

29. 50,000 gallons x 8.88 x 24 (84-60) = 9,996,000 BTU's

Gallons ÷ 3 ÷ # of Bathers = Days

30. 950 gallons ÷ 3 ÷ 23 = 14 Days

31. 1350 gallons ÷ 3 ÷ 63 = 7 Days

pH + TF + CF + AF - TDSF = Saturation Index

32. 7.6 + 0.9 + 2.2 + 2.2 - 12.1 = 0.8 SI = +0.8, Scale Forming

pH + TF + CF + AF - TDSF = Saturation Index

33. 7.0 + 0.7 + 1.6 + 1.7 - 12.2 = -1.2 SI = -1.2, Corrosive

pH + TF + CF + AF - TDSF = Saturation Index

34. 7.0 + 0.5 + 1.3 + 1.4 - 12.1 = -1.9SI = -1.9, Corrosive.