Question

A can complete a certain work in 35 days and B can complete the same work in 15 days. They worked together for 7 days, then B left the work. In how many days will B alone complete 20% of the remaining work?

• A. 7
• B. 1
• C. 1/7
• D. 3/7

Answer 1

Answer:

B. 1

Efficiency of A is 3

and Efficiency of B is 7

They work together for 7days .

Total efficiency of A and B is 10 $=10\times{7}=70 work completed.

Remaining Work = 105-70

$=35$

20% of the remaining work means $=35\times{\frac{20}{100}}$

$=7 work$

B take to complete 7 work for alone in $\frac{7}{7}=1day$