Q9 of 80 Page 56

A and B together can finish a piece of work in 12 days. If ‘A’ alone can finish the same work in 20 days, in how many days B alone can finish it?

Let the number of days taken by B to finish the work be x.

Number of days taken by A to finish the work = 20.


Number of days taken by A and B together = 12.


According to the given condition,



⇒ (Transposing to RHS)


(LCM of 12 and 20 is 60)



⇒ x = 30


∴ B alone can finish the work in 30 days.


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