Question

A can do a piece of work in 8 days and B alone can do the same work in 10 days.A and B agreed to do the work together for Rs.720.With the help of C,they finished the work in 4 days.How much C is to be paid?

• A. Rs.72
• B. Rs.82
• C. Rs.70
• D. Rs.80

Answer 1

The correct option is A Rs.72

C's 1 day work $=\frac{1}{4}-(\frac{1}{8}+\frac{1}{10})$
$=\frac{1}{4}-\frac{9}{40}\Rightarrow \frac{1}{40}$
A's wage " b"s wage " C's wage = $\frac{1}{8}:\frac{1}{10}:\frac{1}{40}=5:4:1$
$\therefore$ C's share (for 4 days)$=\frac{1}{10}\times 720=72$
=Rs.72