### Question Detail

# A tap can fill a tank in 6 hours. After half the tank is filled then 3 more similar taps are opened. What will be total time taken to fill the tank completely.

- 2 hours 30 mins
- 2 hours 45 mins
- 3 hours 30 mins
- 3 hours 45 mins

**Answer: ** Option **D**

**Explanation:**

Half tank will be filled in 3 hours

Lets calculate remaining half,

Part filled by the four taps in 1 hour = 4*(1/6) = 2/3

Remaining part after 1/2 filled = 1-1/2 = 1/2

\begin{aligned}

\frac{2}{3}:\frac{1}{2}::1:X \\

=> X = \left( \frac{1}{2}*1*{3}{2} \right) \\

=> X = \frac{3}{4} hrs = 45 \text{ mins} \\

\end{aligned}

Total time = 3 hours + 45 mins = 3 hours 45 mins