If Harris and Tommy work together on a project, they will complete it in 12 days. If Tommy were to work with William on the same project, they will take a day longer. If William and Isaac work together, they will take 100% more time than Harris and Tommy. If Harris and Isaac were to work together, how many more days will they take to complete the project compared to Tommy and William working together?
Time taken by Harris and Tommy in percent = 100%
Time taken by William and Isaac = 100% + 100% = 200%

Time taken by Harris and Tommy = 12 days ---- (1)
Time taken by Tommy and William = 13 days ---- (2)
Time taken by William and Isaac = 200% x 12 = 24 days ---- (3)

(1) + (2) + (3)
Harris + Tommy + Tommy + William + William + Isaac → 12 + 13 + 24 = 49 days
Harris + 2 (Tommy + William) + Isaac → 49 days
Harris + Isaac + 2 x 13 → 49 days
Harris + Isaac → 49 - 26 = 23 days

More days to complete the project for Harris and Isaac compared to Tommy and William
= 23 - 13
= 10

Answer(s): 10