Long Time to Fill the Tub

A water tub holds 73 gallons; the pipe which fills it usually admits 7 gallons in 5 minutes; and the tap discharges 20 gallons in 17 minutes. Now supposing these both be carelessly left open, and the water to be turned on at 4 o'clock in the morning; a servant, at 6, finding the water running, closes the tap; in what time after this accident will the tub be full?

A New and Complete System of Arithmetic, Nicolas Pike, 1788

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