A does half as much work as B in `3/4`th of the time. If together they take 18 day to complete the work. In how many days can B complete the work alone.

Explanation

Let `B` take `x` days in completing the work.

`:.` Work done by `B` in one day `= 1/x`

Now, `A` does half of the work than `B` in `3/4`th of `B` time.

`:.` Work done by `A` in one day `= (1/(2x))/(3/4) = 2/(3x) `

Both of them together complete that work in `18` days.

`:. 1/x+2/(3x) = 1/18`

`=>5/(3x) = 1/18`

`=>3x=90`

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