Question
A boat takes 7 hours to cover 294 km upstream and 9
hours to cover 486 km downstream. Find the time taken by the boat to cover 720 km upstream and 616 km downstream if speed of boat in still water is increased by 4 km/h and speed of stream is decreased by 2 km/h.Solution
Upstream speed = 294/7 = 42 km/h Downstream speed = 486/9 = 54 km/h Speed of boat in still water = (42 + 54)/2 = 48 km/h Speed of stream = (54 – 42)/2 = 6 km/h Increased speed of boat in still water = 48 + 4 = 52 km/h Decreased speed of stream = 6 – 2 = 4 km/h Required time taken = 720/(52 – 4) + 616/(52 + 4) = 15 + 11 = 26 hours
Which trap crop used for red hairy caterpillar in Groundnut?
Azolla is used in cultivation of:
In onion, smell occurs due to the presence of?
How many calvin cycles are required to produce one molecule of glucose?
In which group of insects is the gizzard characterized by having four mobile lips with spines useful in staining procedures?
Which among the following is the oil body formed in the Endoplasmic Reticulum?
Microbodies associated with mitochondria and chloroplasts containing the enzyme glycolate oxidase are known as
In anaerobic respiration which enzyme is used while converting pyruvic acid to alcohol?
In the context of irrigation scheduling, what does the “IW/CPE ratio” represent?
The coriander flower is:
Relevant for Exams:
