Question
Three pipes P, Q and R can fill a cistern in 40 minutes,
80 minutes and 120 minutes, respectively. Initially, all the pipes are opened. After how much time (in minutes) should the pipes Q and R be turned off so that the cistern will be completely filled in just half an hour?Solution
Assume total work = 240 units (LCM of 40, 80, 120).
Efficiencies: P = 6 units/min, Q = 3 units/min, R = 2 units/min. Let Q and R be turned off after x minutes. Work in first x minutes = (6 + 3 + 2 ) × x = 11x Work in remaining 30 − x minutes by P = 6(30 − x) 11 x + 6 ( 30 − x ) = 240 ⇒ 11 x + 180 − 6 x = 240 ⇒ 5 x = 60 ⇒ x = 12
The “Nutrient Index” concept in soil fertility assessment was introduced by:
The Phenomenon of inheritance of linked genes in same linkage group is called as
Which of the following statement is not correct about the facilitated diffusion?
Water movement under unsaturated soil conditions is mainly driven by_____
Which insect lays eggs in guava fruits, causing damage and rendering them unmarketable?
In furrow irrigation, which factor mainly influences the uniform distribution of water?
Karonda is a rich source of
The process of loss of water from plant is
Why are insects considered among the most successful organisms on Earth in terms of survival and proliferation across ecosystems?
In which part of India the shifting cultivation, locally known ‘Jhuming’ is widely practiced?
Relevant for Exams:
