If Layla and Harris work together on a project, they will complete it in 10 days. If Harris were to work with Evan on the same project, they will take a day longer. If Evan and Tommy work together, they will take 200% more time than Layla and Harris. If Layla and Tommy were to work together, how many more days will they take to complete the project compared to Harris and Evan working together?
Time taken by Layla and Harris in percent = 100%
Time taken by Evan and Tommy = 100% + 200% = 300%

Time taken by Layla and Harris = 10 days ---- (1)
Time taken by Harris and Evan = 11 days ---- (2)
Time taken by Evan and Tommy = 300% x 10 = 30 days ---- (3)

(1) + (2) + (3)
Layla + Harris + Harris + Evan + Evan + Tommy → 10 + 11 + 30 = 51 days
Layla + 2 (Harris + Evan) + Tommy → 51 days
Layla + Tommy + 2 x 11 → 51 days
Layla + Tommy → 51 - 22 = 29 days

More days to complete the project for Layla and Tommy compared to Harris and Evan
= 29 - 11
= 18

Answer(s): 18