Samira can do a piece of work in 9 days. Sujata can do of the same work in 3 days. If Samira worked alone for 2 days and left, then in how many days can Sujata alone complete the remaining work?
Show answer & explanation
Correct answer: D
Explanation
The correct answer is option 4 i.e. 7 days.
Concept Used:
Total work = Number of days × Efficiency
Calculations:
Samira can do the work in 9 days
Sujata can do (1/3) work in 3 days
Sujata can do the whole work in 3 × 3 = 9 days.
Total work = LCM of (9, 9) = 9 units
Efficiency of Samira = Efficiency of Sujata = 9/9 = 1 unit/day
Samira worked for 2 days, the amount of work completed = 2 × 1 = 2 units
Remaining work = 9 - 2 = 7 units
Now, the time taken by Sujata to complete the remaining work = 7/1 = 7 days
Hence the required time is 7 days.