A completes a piece of work in 4 days and B completes it in 6 days. How long will it take to complete the same piece of work if they both work together?
- A2
5
2
days - B3 days
- C2
2
1
days - D4 days
Solution & Step-by-step Explanation
Time taken by A=4 days
Time taken by B=6 days
Let the total work be the LCM of 4 and 6, which is 12 units.
Efficiency of A=
4
12
=3 units/day
Efficiency of B=
6
12
=2 units/day
Combined efficiency of A and B=3+2=5 units/day
Time taken by both working together =
Combined Efficiency
Total Work
=
5
12
=2
5
2
days.
Time taken by B=6 days
Let the total work be the LCM of 4 and 6, which is 12 units.
Efficiency of A=
4
12
=3 units/day
Efficiency of B=
6
12
=2 units/day
Combined efficiency of A and B=3+2=5 units/day
Time taken by both working together =
Combined Efficiency
Total Work
=
5
12
=2
5
2
days.