Question 206564: I need help making a system of equations based on a word problem, here is the problem:"At the hardware store, Leslie bought 2 boxes of nails and 3 boxes of screws and paid $13.95 before tax. Michael bought 4 boxes of nails and 1 box of screws and paid $12.15 before tax. Find the cost of a box of nails and the cost of a box of screws.
Answer by stanbon(75887)   (Show Source):
You can put this solution on YOUR website! At the hardware store, Leslie bought 2 boxes of nails and 3 boxes of screws and paid $13.95 before tax. Michael bought 4 boxes of nails and 1 box of screws and paid $12.15 before tax. Find the cost of a box of nails and the cost of a box of screws.
-------------------------------------------------
Equations:
2n + 3s = 1395 cents
4n + s = 1215 cents
---------------------------------
Multiply thru the 1st equation by 2:
4n + 6s = 2790
---
Subtract the 2nd equation from this modified 1st equation:
5s = 1575
s = 315 cents = $3.15 (price of a box of screws)
---
Substitute to solve for "n"
4n + 315 = 1215
4n = 900
n = 225 = $2.25 (price of a box of nails)
===============================================
Cheers,
Stan H.
|
|
|
