SOLUTION: 5 cups of coffee and 4 cups of tea cost $26.80 whereas 7 cups of coffee and 6 cups of tea cost $38.60.Find the difference between the cost of 1 cup of coffee and 1 cup of tea

Algebra ->  Coordinate Systems and Linear Equations  -> Linear Equations and Systems Word Problems -> SOLUTION: 5 cups of coffee and 4 cups of tea cost $26.80 whereas 7 cups of coffee and 6 cups of tea cost $38.60.Find the difference between the cost of 1 cup of coffee and 1 cup of tea      Log On


   

Question 1127411: 5 cups of coffee and 4 cups of tea cost $26.80 whereas 7 cups of coffee and 6 cups of tea cost $38.60.Find the difference between the cost of 1 cup of coffee and 1 cup of tea
Answer by Boreal(15235) About Me  (Show Source):
You can put this solution on YOUR website!
c and t are the variables
5c+4t=26.80
7c+6t=38.60
multiply top by 3
15c+12t=80.40 and bottom by -2
-14c-12t=-77.20
c=$2.80
therefore 14+4t=26.80, 4t=12.80 and t=$3.20
this checks in the second equation
The difference between the two prices is $0.40, with tea more expensive.