Question 102920
12X+9(100-X)=11.25*100
12X+900-9X=1125
3X=1125-900
3X=225
X=225/3
X=75 POUNDS OF $12 COFFEE IS NEEDED.
100-75=25 POUNDS OF $9 COFFEEE IS NEEDED.
PROOF
12*75+9*25=1125
900+225=1125
1125=1125