alleryThe efficiency of A and B is in the ratio 4:5 and together they need 20 days. A alone needs
A40 days
B36 days
C50 days
D45 days
Answer & Solution
Correct answer: D. 45 days
Total work is 9 units x 20 days = 180 units, and A does 4 units a day, so 45 days.
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