Assisants are needed to prepare for preparation. Each helper can make either 2 large cakes or 35 small cakes/hour. The kitchen is available for 3hours and 20 large cakes and 700small cakes are needed. How many helpers are required?	Choose one:  A) 9  B) 10  C) 13  D) 16  E) 18

Rationale: 20 large cakes will require the equivalent of 10 helpers working for one hour . 700 small cakes will require the equivalent of 20 helpers working for one hour . this means if only one hour were available we would need 30 helpers . but since three hours are available we can use 10 helpers . b
Answer: B