A and B together can do a piece of work in 50 days. If A is 40% less e...
Given:
A and B together can do a piece of work in 50 days.
A is 40% less efficient than B
Concept used:
Total work = Efficiency of the workers × time taken by them
Calculation:
Let the efficiency of B be 5a
So, efficiency of A = 5a × 60%
⇒ 3a
So, total efficiency of them = 8a
Total work = 8a × 50
⇒ 400a
Now,
60% of the work = 400a × 60%
⇒ 240a
Now,
Required time = 240a/3a
⇒ 80 days
∴ A can complete 60% of the work working alone in 80 days.
A and B together can do a piece of work in 50 days. If A is 40% less e...
To solve this problem, let's assume that B can complete the work in x days.
Efficiency of A = 100% - 40% = 60% of B.
Let's calculate the efficiency of A and B:
Efficiency of A = 60% of B = (60/100) * B = 0.6B
Efficiency of B = B
Now, let's calculate the work done by A and B in one day:
Work done by A in one day = Efficiency of A * 1 day = 0.6B * 1 = 0.6B
Work done by B in one day = Efficiency of B * 1 day = B * 1 = B
Working together, A and B can complete the work in 50 days. So, in one day, they can complete 1/50th of the work.
Work done by A and B together in one day = 1/50th of the work
Adding the work done by A and B in one day, we get:
0.6B + B = 1/50
Simplifying the equation, we have:
1.6B = 1/50
Dividing both sides by 1.6, we get:
B = 1/50 * 1/1.6
B = 1/80
So, B can complete 1/80th of the work in one day.
Now, let's calculate the number of days it takes for A to complete 60% of the work:
Work done by A in one day = 0.6B
Substituting the value of B, we have:
Work done by A in one day = 0.6 * 1/80 = 1/133.33
To complete 60% of the work, A would require:
(60/100) * (1/133.33) = 1/222.22
So, A working alone can complete 1/222.22 of the work in one day.
To find the number of days required to complete 60% of the work, we divide 1 by 1/222.22:
1 / (1/222.22) = 222.22
Therefore, A working alone can complete 60% of the work in approximately 222.22 days.
However, none of the given options match this answer. So, it seems that there may be an error in the question or options provided.