Aman, Bishnu, and Chintu can each complete 20%, 25%, and 60% of the work in 4 days, 9 days, and 27 days, respectively. If all three begin the work together but Aman stops after 4 days, how many more days will it take for Bishnu and Chintu to finish the remaining work together?

‘Aman’, ‘Bishnu’ and ‘Chintu’ will complete the whole work in 20 days (4/0.20), 36 days (9/0.25) and 45 days (27/0.60) respectively. Let total amount of work = 180 units (LCM of 20, 36 and 45) Amount of work done by ‘Aman’ in one day = 180/20 = 9 units Amount of work done by ‘Bishnu’ in one day = 180/36 = 5 units Amount of work done by ‘Chintu’ in one day = 180/45 = 4 units Amount of work done by ‘Aman’, ‘Bishnu’ and ‘Chintu’ together in 4 days = 4 × (9 + 5 + 4) = 72 units Time taken by ‘Chintu’ and ‘Bishnu’ together to complete the remaining work = (180 – 72)/(5 + 4) = 12 days