Question
‘A’ alone can complete a work in 50 hours. ‘A’
started the work alone and left after working on it for 30 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 = 200 units Then, efficiency of ‘A’ = (200/50) = 4 units/hour Work completed by ‘A’ alone in 30 hours = 4 × 30 = 120 units Remaining work = 200 – 120 = 80 units So, efficiency of ‘B’ = 80/20 = 4 units/hour Therefore, combined efficiency of ‘A’ and ‘B’ = 4 + 4 = 8 units/hour So, time taken by ‘A’ and ‘B’ together to complete the work = (200/8) = 25 hours
Which one of the following statement regarding the sun is correct?
Tendons and Ligaments are
The energy of a photon is proportional to:
Decibel is used to measure the ___________.
Motion that repeats itself after some period of time, is called ______ motion.
Who discovered the neutrons?
A person standing on a trolley moving in a straight line throws a stone vertically upward, relative to himself, while facing in the direction of motion....
When acid is added to the indicator- methyl orange, what is the color observed?
Which one among the following fuels is used in gas welding?
Which one among the following statements is not true for Mammals?
