A company produces fruity drinks that contain a percentage of real fruit juice. Drink A contains 10% real fruit juice and Drink B contains 15% real fruit juice. How many liters of real fruit juice would be needed to produce 100 liters of Drink A and 250 liters of Drink B? How many liters of real fruit juice would be needed to produce a liters of Drink A and b liters of Drink B?