• There are two tanks A and B to fill up a water tank. The tank can be filled in 40 min, if both taps are on. The same tank can be filled in 60 min, if tap A alone is on. How much time will tap alone take, to fill up the same tank?
 A) 64 min B) 80 min C) 96 min D) 120 min

 D) 120 min

Part filled by tap A in 1 min = $$\Large \frac{1}{60}$$

Let tap B fills the tank in x min

Then, part filled by tap, B in 1 min = $$\Large \frac{1}{x}$$

According to the question,

= $$\Large \frac{1}{60}$$ + $$\Large \frac{1}{x}$$ = $$\Large \frac{1}{40}$$

= $$\Large \frac{1}{x}$$ = $$\Large \frac{1}{40}$$ - $$\Large \frac{1}{60}$$

=> $$\Large \frac{1}{x}$$ = $$\Large \frac{3-2}{120}$$ => $$\Large \frac{1}{x}$$ = $$\Large \frac{1}{120}$$

Therefore, Tap B can fill the tank in 120 min.

##### Similar Questions
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