🔍 Key Concepts

• Duplex single-acting reciprocating pump – understand what “duplex” and “single-acting” mean for how many displacements per revolution/stroke cycle you get • Pump capacity formula: capacity per stroke = area of piston × stroke length, then multiply by strokes per minute and volumetric efficiency • Unit conversions – converting from cubic inches/minute to gallons per minute (gpm), remembering 1 gallon ≈ 231 in³

💭 Think About

• First, determine how many cylinders are actually delivering water on each stroke in a duplex single-acting pump, and how that affects total displacement per stroke/minute • Calculate the volume displaced by one cylinder for one stroke using the given diameter and stroke length; then scale it up by strokes per minute and number of cylinders, and finally apply the 93% volumetric efficiency • After getting total volume per minute in cubic inches, carefully convert it to gallons per minute and compare to the choices

✅ Before You Answer

• Be sure you are using the correct piston area: (A = \pi d^2 / 4) with d in inches • Confirm whether you multiplied by the correct number of cylinders and delivery strokes for a “duplex single-acting” pump • Double-check your cubic inch to gallon conversion (use 231 in³ = 1 gallon) before selecting the closest answer