If Ella and Hazel work together on a project, they will complete it in 8 days. If Hazel were to work with Alexander on the same project, they will take a day longer. If Alexander and Isaac work together, they will take 100% more time than Ella and Hazel. If Ella and Isaac were to work together, how many more days will they take to complete the project compared to Hazel and Alexander working together?
Time taken by Ella and Hazel in percent = 100%
Time taken by Alexander and Isaac = 100% + 100% = 200%

Time taken by Ella and Hazel = 8 days ---- (1)
Time taken by Hazel and Alexander = 9 days ---- (2)
Time taken by Alexander and Isaac = 200% x 8 = 16 days ---- (3)

(1) + (2) + (3)
Ella + Hazel + Hazel + Alexander + Alexander + Isaac → 8 + 9 + 16 = 33 days
Ella + 2 (Hazel + Alexander) + Isaac → 33 days
Ella + Isaac + 2 x 9 → 33 days
Ella + Isaac → 33 - 18 = 15 days

More days to complete the project for Ella and Isaac compared to Hazel and Alexander
= 15 - 9
= 6

Answer(s): 6