Hazel wants to mix 12 pounds of her special blend coffee that will cost her $12.50 per pound. She uses Columbian and Sumatra coffees which cost her $9.25 and $14.25 per pound.
x - pounds of Columbian coffee; y - pounds of Sumatra coffee. 9.25 x + 14.25 y = 12.50 ( x + y ) x + y = 12 ------------------------------------------- 9.25 x + 14.25 y = 150 x = 12 - y --------------------------------------- 9.25 ( 12 - y ) + 14.25 y = 150 111 - 9.25 y + 14.25 y = 150 5 y = 150 - 111 5 y = 39 y = 39 : 5 y = 7.8 x = 12 - 7.8 x = 4.2 Answer: She needs 4.2 pounds of Columbian coffee and 7.8 pounds of Sumatra coffee.
