If Rachel and Samantha work together on a project, they will complete it in 7 days. If Samantha were to work with Andrew on the same project, they will take a day longer. If Andrew and Christopher work together, they will take 200% more time than Rachel and Samantha. If Rachel and Christopher were to work together, how many more days will they take to complete the project compared to Samantha and Andrew working together?
Time taken by Rachel and Samantha in percent = 100%
Time taken by Andrew and Christopher = 100% + 200% = 300%

Time taken by Rachel and Samantha = 7 days ---- (1)
Time taken by Samantha and Andrew = 8 days ---- (2)
Time taken by Andrew and Christopher = 300% x 7 = 21 days ---- (3)

(1) + (2) + (3)
Rachel + Samantha + Samantha + Andrew + Andrew + Christopher → 7 + 8 + 21 = 36 days
Rachel + 2 (Samantha + Andrew) + Christopher → 36 days
Rachel + Christopher + 2 x 8 → 36 days
Rachel + Christopher → 36 - 16 = 20 days

More days to complete the project for Rachel and Christopher compared to Samantha and Andrew
= 20 - 8
= 12

Answer(s): 12