X can do a piece of work in 25 days and Y can finish it in 20 days. How long will X and Y take to complete the work together?
Answers
Given:-
- Time taken for X to do complete work = 25 days
- Time taken for Y to do complete work = 20 days
To find:-
- Time taken for X and Y to complete the work together.
Answer:-
Complete/full work is considered as 1.
For X:-
Work by X in 25 days = 1 (complete/full)
→ Part of work done by X in 1 day = 1/25
For Y:-
Work by Y in 20 days = 1 (complete/full)
→ Part of work done by Y in 1 day = 1/20
For X and Y working together:-
Part of work done by X and Y together in 1 day = (Part of work done by X in 1 day) + (Part of work done by Y in 1 day)
→ Part of work done by X and Y together in 1 day = (1/25) + (1/20)
→ Part of work done by X and Y together in 1 day = (4 + 5)/100
→ Part of work done by X and Y together in 1 day = 9/100
Now,
Time taken by X and Y together to do 9/100 part of work = 1 day
→ Time taken by X and Y together to do 1 (complete/full) work = 100/9 days
→ Time taken by X and Y together to do 1 (complete/full) work = 11⅑ days Ans.