Question
A and B together can finish a job in 12 days. B alone
takes 30 days. How long will A and C together take to finish the same job if C does one-fourth of A’s work?Solution
ATQ,
Work rates: A + B = 1/12 B = 1/30 So A = 1/12 – 1/30 = (5 – 2)/60 = 3/60 = 1/20 C = 1/4 of A = 1/80 A + C = 1/20 + 1/80 = (4 + 1)/80 = 5/80 = 1/16 Hence, 16 days
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