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← Back to MathHow to Use a Pie Wheel
Page 3 of 8
Jump to a Lesson
1. Pie Wheel Basics2. Find the Top3. Find a Bottom4. Place the Numbers5. Choose a Wheel6. Three-Part Wheel7. Find the Dose8. Guided Practice

Lesson 3

Finding a Bottom Section: Divide

Cover a bottom section. The top is divided by the section that is left.
Detention TimeTap a section to cover the quantity you want to find.

What remainsTime = Volume ÷ Flow

Now the unknown is below the line. Cover Time: Volume is left above Flow, so divide the top by the section that is left.

Time = Volume ÷ Flow

120,000 gal ÷ 1,000 gal/min = 120 min

Tap Volume, then Flow, on the wheel. The formula changes with the section you cover; the wheel stays the same.

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