Correct Answer - Option 2 : 12 days
Given:
Rahul can complete a work in 15 days
Suman can complete the same work in 20 days,
Rahul hep Suman only on alternate days
Concept used:
Total work = Time × Efficiency
Calculation:
|
|
Time
|
Total work
|
Efficiency
|
|
Rahul
|
15
|
|
4
|
|
|
|
60
|
|
|
Suman
|
20
|
|
3
|
Work completed for the first day by Suman = 3
Work completed for the second day by Rahul + Suman
⇒ 4 + 3 = 7
Work completed in 2 days
⇒ 3 + 7 = 10
Time taken
⇒ 60/10 = 6
Total time
⇒ 6 × 2 = 12 days
∴ Total time taken 12 days.
