Adam can do a piece of work in 10 days, and Brandon can do the same work in 20 days. With the help of Catty, they finished the work in 4 days. Catty can do the work in how many days, working alone?

A can do work in 20 days. Then, he is assisted by B to complete the remaining work in 12 days. In how much time can B alone do the work?

When they work alone, B needs 60% more time to finish a piece of work than A does. Both of them finish the work in the following manner: B works alone till one-fourth of the work is done, then A and B work together for 12 days, and finally, A works alone to complete the remaining 10% of the work. In how many days can A alone finish the entire work?

X and Y can do a piece of work in 20 days and 12 days respectively. X started the work alone and then after 4 days Y joined him until the completion of the work. How long did the work last?

A and B can complete a work in 15 days and 10 days respectively. They started doing the work together but after 2 days B had to leave and A alone completed the remaining work. The whole work was completed in :8 days10 days12 days15 days

Samuel can do a piece of work in 12 days and Bruce can do it in 6 days. If Carl, who can do the work in 16 days, joins them, then how long will they take to together complete the work?  Ops:   A. 7/8 days    B. 16/5 days    C. 24/5 days    D. 13/25 days