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Arun and Varun can finish a task in 6 hours and 4 hours, respectively. Arun started
the work alone and worked for 2 hours. He was then joined by Varun. Find the total
time taken to complete the task.
Answers
Answer:
4 hours 40 minutes
Step-by-step explanation:
Hours taken by Arun to complete the task= 6 hours.
this means the portion of work he does in 1 hour (capacity)= 1/6
similarly, that of Varun = 4 hours.
so portion of work done by Varun in 1 hour = 1/4
Now Arun worked for 2 hours, So portion of work completed by him in that 2 hours= 2×(Capacity of Arun)
= 2×1/6
= 1/3
Hence the portion of work left to do = 1-1/3
= 2/3
The rest of the work is done by Varun. So time taken by Varun to complete the task ,
=> x(hours) × 1/4 (capacity of Varun) = 2/3 (remaining portion of work)
=> x × 1/4 = 2/3
=> x = 2/3×4/1
=> x = 8/3
=> x = 2+2/3 hours
=> x= 2 hours 40 mins
Hence total time taken to complete the work by Varun and Arun = 2(Arun) + 2 hours 40 mins ( Varun)
= 4 hours 40 minutes