P, Q and R can complete a work in 24, 6 and 12 days respectively. The work will be completed in --- days if all of them are working together. Choose the correct option.
A) 2 B) 3 3⁄7 C) 4 ¼ D) 5 E) 5 ¼
Explanation :   Work done by P in 1 day = 1/24   Work done by Q in 1 day = 1/6   Work done by R in 1 day = 1/12   Work done by P,Q and R in 1 day = 1/24 + 1/6 + 1/12 = 7/24   =&gt; Working together, they will complete the work in 24/7 days = 3 3⁄7 days   Answer : Option 3 3⁄7
<result>B</result>
P, Q and R can complete a work in 24, 6 and 12 days respectively. The work will be completed in --- days if all of them are working together.