algebra
posted by lauren on .
Sarah blends coffee for TastiDelight. She needs to prepare 170 lbs of blended coffee beans selling for $3.59 per pound. She plans to do this by blending together a highquality bean costing $5.00 per pound and a cheaper bean at $2.00 per pound. To the nearest pound, find how much highquality coffee bean and how much cheaper coffee bean she should blend.

Blend:
X lbs of hiquality beans.
Y lbs of cheaper beans.
Eq1: X + Y = 170 lbs.
Eq2: 5x + 2y = 3.59*170 = $610.30.
Multiply Eq1 by 2 and add the Eqs:
2x  2y = 340
+5x + 2y = 610.3
Sum: 3x = 270.3,
X = 90 lbs.
90 + y = 170,
Y = 170  90 = 80 lbs.