A can complete a task in 10 days and B can complete it in 15 days. Together, how long will they take?
Correct answer
B. 6 days
Why
Combined rate = 1/10 + 1/15 = 1/6, so they finish in 6 days.
RBI Assistant / Numerical Ability
RBI Assistant Time and Work practice questions
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Time and Work questions with answers
Backup practice: A can complete a task in 10 days and B can complete it in 15 days. Together, how long will they take?
Correct answer
B. 6 days
Why
Combined rate = 1/10 + 1/15 = 1/6, so they finish in 6 days.
A can finish a task in 13 days and B can finish it in 19 days. How long will they take working together?
Correct answer
C. 247/32 days
Why
Combined rate = 1/13 + 1/19 = 32/247. Time = 247/32 = 247/32 days.
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