For a project, Party A and Party B work together for 20 days, and Party A has worked together for 2 days after 3 days to complete 1 / 5 of the whole project. How many days does it take for Party A and Party B to work alone? Remember, ”Three days later, it was followed by "three days later, B followed". Just understand.

For a project, Party A and Party B work together for 20 days, and Party A has worked together for 2 days after 3 days to complete 1 / 5 of the whole project. How many days does it take for Party A and Party B to work alone? Remember, ”Three days later, it was followed by "three days later, B followed". Just understand.

After three days, Jia has been working with him for two days
Conversion: Party A and Party B cooperate for 2 days and party a work for 3 days
A: 3 (1 / 5-1 / 20x2) = 30 (days)
Party B: 1 / 20-1 / 30 = 60 (days)