Question

A is 3 times as fast as b and is thrrefore able to finish work in 60 days less than that of



b. How long will they take if both work together

Answer 1

Assume number of days taken by A =x days, then number of days taken by B =3x days (as A is thrice as efficient as B).

According to the question,

3x - x = 60 days, hence x = 30 days

SO, number of days taken by A = 30 days, and number of days taken by B = 90 days

Assume total units of work = LCM (30 , 90) units = 90 units

So, work done by A in one day = (90/30) = 3 units per day AND

work done by B in one day = (90/90) = 1 unit per day.

Hence total units done by both A and B together in one day = 4 units per day

So, total number of days taken by both of them = Total work / Number of units done in one day = 90 / 4 = 22.5 days.

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18.5k Views ·

A is twice as good a workman as B and together they finish a piece of work in 18 days. In how many days can A alone finish the work?

John is twice as good as Michael and together they finish a piece of work in 18 days in how many days Michael alone will finish the job?

A is twice as efficient as B and can complete a job 30 days before B. How quickly can they complete a job together?

If A can complete a piece of work in 12 days and B is 60% more efficient than A, then in how many days will B complete the same work?

The efficiency of A is half of B and C together, and the ratio of efficiency of B and C is 5:4. If they complete a work in 120 days (worked) together, then in how many days can C complete the work?

Form the problem,

Let assume A produces 3 units per day

And B produces 1 unit per day

A takes 'x' days and

B takes x + 60 days

Now we compare both works

A. B

3. 1

X. X+60

1*(x+60)= 3(x)

X= 30

Total work = 3*30= 90

When both A and B work together

= Total work / (efficiency of (A +B))

= 90/(3+1)

= 22.5 days

Hence , they can finish work in 22.5 days .

7k Views · · Answer requested by

Let B takes x days to finish the whole work and A takes x-60 days to complete same work.

It is given that A is thrice good workman as compare to B.

Thus part of work done by A in one day =3 times work done by B in one day =>1/(x-60)=3/x

=>3x-180=x=>2x=180=>x=90

one day work of A and B=1/30+1/90=4/90=2/45=1/22.5

Hence in 22.5 days are required to finish the work if A and B work together.