SOLUTION: plz help me to sove this problem 5 Fuji apples and 8 Sunkist oranges cost $17.20 while 3 Fuji apples and 9 Sunkist oranges cost $13.05. Find the costs of a Fuji apple and a Sunki

Algebra ->  Coordinate Systems and Linear Equations  -> Linear Equations and Systems Word Problems -> SOLUTION: plz help me to sove this problem 5 Fuji apples and 8 Sunkist oranges cost $17.20 while 3 Fuji apples and 9 Sunkist oranges cost $13.05. Find the costs of a Fuji apple and a Sunki      Log On


   

Question 392186: plz help me to sove this problem
5 Fuji apples and 8 Sunkist oranges cost $17.20 while 3 Fuji apples and 9 Sunkist oranges cost
$13.05. Find the costs of a Fuji apple and a Sunkist orange respectively
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
5 Fuji apples and 8 Sunkist oranges cost $17.20
---
5f + 8s = 17.20
==========================
while 3 Fuji apples and 9 Sunkist oranges cost $13.05.
3f + 9s = 13.05
==========================
Find the costs of a Fuji apple and a Sunkist orange respectively
====================
Multiply thru the 1st equation by 3.
Multiply thru the 2nd equation by 5.
------------------------------
15f + 24s = 3*17.20
15f + 45s = 5*13.05
---------------------------
Subtract 1st from 2nd and solve for "s":
21s = 13.65
s = 0.65 or 65 cents (price of a Sunkist orange)
----
Substitute into 3f + 9s = 13.05 to solve for "f":
3f + 9*0.65 = 13.05
3f = 7.20
f = $2.40 (price of a Fuji apple)
============
Cheers,
Stan H.