alleryRavi alone digs a trench in 10 days and Sunil alone in 15 days. Both together need
A8 days
B6 days
C5 days
D7 days
Answer & Solution
Correct answer: B. 6 days
Together they do 1/10 + 1/15 = 5/30 = 1/6 of the trench each day, so 6 days.
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