Question

A can do a piece of work in 12 days and B can do it in 15 days. A starts the work and does it for 3 days. The remaining work is done by B alone. In what time did B finish the remaining work?
Answer given = 11¼ = 45/4 pleaseeeee give step by step explanation​

Answer 1

Answer:

Work done by A and B in 5 days

= 5\left ( \frac{1}{12}+\frac{1}{15} \right ) = 5\left ( \frac{5+4}{60} \right )

= 5\times \frac{9}{60} = \frac{9}{12} = \frac{3}{4}

Remaining work = 1-\frac{3}{4} = \frac{1}{4}

∴ Time taken by A = \frac{1}{4}\times 12 = 3\ days