Question 108655
Let n=# of lbs of $9/lb; t=# of lbs of $12/lb
.
A) n+t=100
B) 9n+12t=1125
.
A) n=100-t
B) 9(100-t)+12t=1125
900-9t+12t=1125
3t+900=1125
3t+900-900=1125-900
3t=225
t=75 lbs
n=25 lbs
Always check:
9*25+12*75=1125 true
.
Ed