Question

Maxwell House Coffee contains 13% Columbian coffee beans by volume while
Folgers Coffee contains 21% Columbian coffee beans by volume. What
quantity of each brand must be combined to produce 70 kg of a blend that
contains 19% Columbian coffee beans?.

Answer 1

x kg of Maxwell House coffee contains 0.13x kg of Columbian beans.

y kg of Folgers contains 0.21y kg of beans.

You want a mixture weighing 70 kg, so

x + y = 70

You also want this blend to consist of 19% Columbian beans, or 0.19 (70 kg) = 13.3 kg, so

0.13x + 0.21y = 13.3

Solve for x and y :

x + y = 70   ===>   y = 70 - x

0.13x + 0.21y = 13.3   ===>   0.13x + 0.21 (70 - x) = 13.3

0.13x + 14.7 - 0.21x = 13.3

14.7 - 13.3 = 0.21x - 0.13x

1.4 = 0.08x

x = 17.5

y = 52.5