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Lesson 7

Three Bottom Sections: Finding the Dose

To find one bottom section of a three-part wheel, multiply the other two, then divide the top by that result.
Dosage / Feed at 100% PurityTap a section to cover the quantity you want to find.

What remainsDose = Feed ÷ Flow ÷ Factor

  1. 1
    Identify unknown

    Dose

  2. 2
    Choose wheel

    Dosage / Feed at 100% Purity

  3. 3
    Place values

    Feed: 50.04 lb/day · Flow: 1.5 MGD · Factor: 8.34

  4. 4
    Cover unknown

    Dose is a bottom section. Multiply the other two bottom sections (1.5 × 8.34 = 12.51), then divide the top by that result.

  5. 5
    Solve

    50.04 lb/day ÷ 12.51 = 4 mg/L

  6. 6
    Check units

    The answer is in mg/L, the units of the Dose section.

This wheel uses a 100% purity example. A lower-purity product needs the full purity adjustment in Dosage & Feed.