Three taps P, Q and R separately can fill a t | vedclass

Name: Exam Paper Generator | JEE NEET Paper Generator | Vedclass
Brand: Vedclass
Rating: 5 (35 reviews)

Question

(D) Let the total capacity of the tank be the $LCM$ of $4, 8, 12,$ and $10$,which is $120$ units.Efficiency of $P = 120/4 = 30$ units/hr.Efficiency of

Vedclass · Accepted Answer

$P, Q$ and $S$ are opened

Vedclass · Answer

(D) Let the total capacity of the tank be the $LCM$ of $4, 8, 12,$ and $10$,which is $120$ units.Efficiency of $P = 120/4 = 30$ units/hr.Efficiency of $Q = 120/8 = 15$ units/hr.Efficiency of $R = 120/12 = 10$ units/hr.Efficiency of $S = -120/10 = -12$ units/hr (negative because it empties).$(i)$ $Q$ opened alone: Time $= 120/15 = 8$ hours.(ii) $P$ and $S$ opened: Net efficiency $= 30 - 12 = 18$ units/hr. Time $= 120/18 = 6.67$ hours.(iii) $P, R$ and $S$ opened: Net efficiency $= 30 + 10 - 12 = 28$ units/hr. Time $= 120/28 = 4.28$ hours.(iv) $P, Q$ and $S$ opened: Net efficiency $= 30 + 15 - 12 = 33$ units/hr. Time $= 120/33 = 3.64$ hours.Comparing the times: $3.64 < 4.28 < 6.67 < 8$. Therefore,option $(d)$ takes the least time.

Three taps $P, Q$ and $R$ separately can fill a tank completely in $4, 8$ and $12$ hours respectively. Another tap $S$ can empty the filled tank in $10$ hours. Which of the following combinations will fill the empty tank in the least amount of time?

Similar Questions

Two pipes can fill an empty tank separately in $24$ $minutes$ and $40$ $minutes$ respectively,and a third pipe can empty $30$ $gallons$ of water per $minute$. If all three pipes are opened,the empty tank becomes full in one $hour$. The capacity of the tank (in $gallons$) is:

$A, B$ and $C$ are three pipes connected to a tank. $A$ and $B$ together fill the tank in $6$ $hrs$. $B$ and $C$ together fill the tank in $10$ $hrs$,and $C$ and $A$ together fill the tank in $7 \frac{1}{2}$ $hrs$. In how much time (in $hours$) will $A, B$ and $C$ fill the tank together?

Two pipes,$A$ and $B,$ can separately fill a tank in $6$ $hours$ and $8$ $hours,$ respectively. Both the pipes are opened together,but $1 \frac{1}{2}$ $hours$ later pipe $A$ is turned off. How much time (in $hours$) will it take to fill the tank?

$A$ cistern is filled by two taps $A$ and $B$. Tap $A$ can fill it in $20$ $minutes$ and tap $B$ in $25$ $minutes$. Both the taps are kept open for $5$ $minutes$ and then the second tap $(B)$ is turned off. The cistern will be completely filled in another:

$A$ pipe can fill a tank with thrice the speed of another pipe. If both the pipes together take $36$ $min$ to fill an empty tank completely,then how much time will it take for the slower pipe to fill the tank alone?

Vedclass Test Series

Exam Paper Generator

Online Exam Module