alleryStart learning →A alone finishes a job in 6 days, B in 12. At constant independent rates, how long do they need together?
A3 days
B4 days
C9 days
D18 days
Answer & Solution
Correct answer: B. 4 days
Their daily work rates add to 1/6 + 1/12 = 1/4 of the job, so together they need four days.
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