A can do a piece of work in 4 days and B can complete the same work in 12 days. What is the number of days required to do the same work together?

A) 2 days

B) 3 days

C) 4 days

D) 5 days

Correct answer:
B) 3 days

Description for Correct answer:

A's 1 day's work = 1/ 4

B's 1 day's work= 1/12

(A + B)'s s 1 day's work = \( \Large\frac{1}{4} + \frac{1}{12} \)

\( \Large\frac{3 +1}{12} = \frac{4}{12} = \frac{1}{3} \)

Days required by A and B together to do the work

= 1 / (A + B)'s 1 day's work = 3 days



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