alleryTwo bricklayers need 14 and 21 days respectively for a wall. Working together they need
A8.4 days
B8 days
C7 days
D9 days
Answer & Solution
Correct answer: A. 8.4 days
1/14 + 1/21 = 5/42 per day, so the wall takes 42/5 = 8.4 days.
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