Question 1129099
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A solution using logical reasoning instead of formal algebra....<br>
The hot water faucet takes 4 times as long as the cold water faucet to fill the tub.<br>
That means that in filling the tub together in 3 minutes, the cold water faucet fills 4/5 of the tub.<br>
So to fill the whole tub by itself the cold water faucet has to work 5/4 as long; 3 minutes times 5/4 is 15/4 minutes, or 3 minutes 45 seconds.