If Christopher and Evelyn work together on a project, they will complete it in 10 days. If Evelyn were to work with Jack on the same project, they will take a day longer. If Jack and Alexander work together, they will take 70% more time than Christopher and Evelyn. If Christopher and Alexander were to work together, how many more days will they take to complete the project compared to Evelyn and Jack working together?
Time taken by Christopher and Evelyn in percent = 100%
Time taken by Jack and Alexander = 100% + 70% = 170%

Time taken by Christopher and Evelyn = 10 days ---- (1)
Time taken by Evelyn and Jack = 11 days ---- (2)
Time taken by Jack and Alexander = 170% x 10 = 17 days ---- (3)

(1) + (2) + (3)
Christopher + Evelyn + Evelyn + Jack + Jack + Alexander → 10 + 11 + 17 = 38 days
Christopher + 2 (Evelyn + Jack) + Alexander → 38 days
Christopher + Alexander + 2 x 11 → 38 days
Christopher + Alexander → 38 - 22 = 16 days

More days to complete the project for Christopher and Alexander compared to Evelyn and Jack
= 16 - 11
= 5

Answer(s): 5