Q:

A can do a piece of work in 30 days and B can do the same work in 18 days. B starts the work and continues for 6 days alone then A joins him. Find in how much time the remaining work gets completed both working together.

• 1
  $$ {7{1\over 3}}$$
• 2
  $$ {7{1\over 4}}$$
• 3
  7$$ {7{1\over 2}}$$
• 4
  $$ {7{1\over 2}}$$
• 5
  None of these