Question

A, B and C complete a work working alone in 10, 15 and 20 days respectively If all of then work together to complete the work what fraction of the work would have done by B?

• A. $\frac{4}{13}$
• B. $\frac{1}{2}$
• C. $\frac{1}{3}$
• D. $\frac{6}{13}$

Answer 1

Answer: (A)

$\frac{4}{13}$

(A+B+C)'s one day's work$=\frac{1}{10}+\frac{1}{15}+\frac{1}{20}=\frac{13}{60}$
Fraction of work done by B$=\frac{\frac{1}{15}}{\frac{13}{60}}=\frac{4}{13}$