Question

2. A and B together can complete a piece of work in 4 days. If A alone can
complete the same work in 12 days, in how many days can B alone complete
that work​

Answer 1

Answer:

Question:-

A and B together can complete a piece of work in 4 days. If A alone can complete the same work in 12 days, in how many days can B alone complete

that work

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Required Answer:-

Given:-

time taken by A alone to complete a work= 12 days.

Time taken by both A and B to complete a work= 4 days.

___________________________

To Find:-

Time taken by B to complete a work= ? days.

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Solution:-

Let B takes x days to complete a work.

A takes 12 days to complete a work-(given).

A's one day work=1/12

B's One day work=1/x

Therefore, (A & B)'s one day work=1/12+1/x -(i)

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As per the given,

if A and B work together than they take 4 days to complete a work.

Therefore, (A & B)'s one day work=1/4-(ii)

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From (i) and (ii),

1/12+1/x=1/4

1x+12/12x=1/4

4(1x+12)=1(12x)

4x+48=12x

48=12x-4x

48=8x

48/8=x

6=x

x=6

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Therefore B takes 6 days to complete a work.

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Hope it help you.