Question
Two pipes X and Y can fill an empty tank in 8 hours and
10 hours, respectively. Pipe Z alone can empty the completely filled tank in 15 hours. Firstly, both pipes X and Y are opened, and after 4 hours, pipe Z is also opened. What will be the total time (in hours) required to completely fill the tank?Solution
Pipe X fills in 8 hours → rate = 1/8 Pipe Y fills in 10 hours → rate = 1/10 Pipe Z empties in 15 hours → rate = 1/15 For the first 4 hours, only X and Y work:(1/8 + 1/10) × 4 = 9/40 × 4 = 36/40 = 9/10 So, 90% of the tank is filled. Now X, Y, and Z work together: (1/8 + 1/10 + 1/15) = 19/120 ​Remaining work = 1 − 9/10 = 1/10​ Time to finish = (1/10)/(19/120) = 12/19 hrs Total time = 4 + 12/19 = 88/19 hrs
Which one among the following statements is correct?Â
Which among the following is produced using ‘Haber Process’?
Inactive Nitrogen and Argon gases are usually used in electric bulbs in order to
A rocket with a lift-off mass 10,000 kg is blasted upwards with an initial acceleration of 5.0 m s–2. Calculate the initial thrust (force) ...
Chemical equation is balanced according to the law of
What is the process of changing a substance directly from solid to gas called ?
Kindly Study the following questions carefully and choose the right answer:
Transpiration is mainly effective during _______ ?
Two billiard balls each of mass 0.02 kg moving in opposite directions with speed 5 m s−1 collide and rebound with the same speed. What is t...
If the phase difference between two points is 120° for a wave with velocity of 360 m/ and frequency 500 Hz, then path difference between the two points...
Consider the following three nuclear reactions:
Wh...
Relevant for Exams:
