Question
‘A’ alone can complete a work in 40 hours. ‘A’
started the work alone and left after working on it for 20 hours. If ‘B’ completed the rest of the work in 20 hours then find the time taken by ‘A’ and ‘B’ together to complete the whole work.Solution
Let the total work = 300 units Then, efficiency of ‘A’ = (300/40) = 7.5 units/hour Work completed by ‘A’ alone in 20 hours = 7.5 × 20 = 150 units Remaining work = 300 – 150 = 150 units So, efficiency of ‘B’ = 150/20 = 7.5 units/hour Therefore, combined efficiency of ‘A’ and ‘B’ = 7.5 + 7.5 = 15 units/hour So, time taken by ‘A’ and ‘B’ together to complete the work = (300/15) = 20 hours
Which among the following irrigation methods involves applying water below the soil surface using a network of perforated pipes?
Concentration of which of the following is high in soil?
Which is a common crop which is grown of natural autopolyploid?
pH suitable for fish pond is ___
Which one the following terminology is used for the process of accumulation of soluble salts at the surface or at some point below the surface of the so...
Proper time of sowing hybrid maize is:
Citrus canker is caused by
If a farmer practices “sugarcane -wheat” the cropping intensity at his farm will be __________ %.
Which of following fruit is most suitable for jelly making
Increase in supply of money leads to:
Relevant for Exams:
