Kenyan = k
$3.50 per pound
Sri Lankan = s
$5.60 per pound
6lbs of blend
$28.35
s+k = 6
3.50k + 5.60s = 28.35
where:
k = lbs of kenyan
s = lbs of Sri Lankan
Solve the system
s+k = 6
3.50k + 5.60s = 28.35
solve the first equation for s:
s = 6-k
Replace in the second equation:
3.50k + 5.60 (6-k) = 28.35
3.50k + 5.60(6)+ 5.60(-k) = 28.35
3.50k + 33.6 - 5.60k = 28.35
3.50k - 5.60k = 28.35-33.6
-2.1k= -5.25
k= -5.25/-2.1
k= 2.5 lbs
Replace k on any equation and solve for s
s+k= 6
s+ 2.5 = 6
s= 6-2.5
s= 3.5 lbs