A Water Faucet Can Fill a Sink in 10 Minutes

question 163

Multiple Choice

A water faucet can fill a sink in 10 minutes, whereas the drain can empty it in 8 minutes. If the sink is full, how long will it take to empty if both the faucet and the drain are open?

• A)10 minutes
• B)80 minutes
• C)40 minutes
• D)18 minutes
• E)9 minutes

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Definitions:

Economies of Scale

Cost advantages that entities attain due to the scale of operation, with costs per unit of output generally decreasing with increasing scale.

Economic Profit

The difference between total revenue and total costs, including both explicit and implicit costs, measuring the performance exceeding opportunity costs.

Short-Run Equilibrium

The condition in which supply and demand are equal at a particular price level, within a short time frame, before all variables have fully adjusted.