|
Question 1109936: A store began selling its line of fall sweaters. On the first day, 6 cotton, 4 orlon, and 5 wool sweaters were sold. On the second day, 3 cotton, 5 orlon, and 8 wool sweaters were sold. On the third day, 4 cotton, 1 orlon and 4 wool sweaters were sold. Total sales for the three days were $395, $505, and $260, respectively. What was the sale price for each sweater?
Thank you!
Answer by Boreal(15235)   (Show Source):
You can put this solution on YOUR website! 6C+4OR+5W=395
3C+5OR+8W=505
4C+1OR+4W=260
1OR=260-4W-4C
substitute
6C+1040-16W-16C+5W=395 or -10C-11W=-645 or 10C+11W=645
3C+1300-20W-20C+8W=505 or -17C-12W=-795 or 17C+12W=795
-120C-132W=-7740 multiplying by -12
187C+132W=8745
67C=1005
C=15
second and third
45+5OR+8W=505; 5OR+8W=460
60+1OR+4W=260; 1OR+4W=200, or -2OR-8W=-400
3OR=60
OR=20
4W=180
W=45
C=$15
OR=$20
W=$45
Matrices can be used as well and probably preferred, although a substitution puts this into 2 equations into 2 unknowns, which can then be solved.
|
|
|
| |
