SOLUTION: On​ Monday, Harold picked up six donuts and two large coffees for the office staff. He paid $ 5.94 .  On​ Tuesday, Melinda picked up four donuts and five large coffees for

Algebra ->  Coordinate Systems and Linear Equations  -> Linear Equations and Systems Word Problems -> SOLUTION: On​ Monday, Harold picked up six donuts and two large coffees for the office staff. He paid $ 5.94 .  On​ Tuesday, Melinda picked up four donuts and five large coffees for      Log On


   

Question 1158747: On​ Monday, Harold picked up six donuts and two large coffees for the office staff. He paid $ 5.94 .  On​ Tuesday, Melinda picked up four donuts and five large coffees for the office staff. She paid $ 7.04 .  What is the cost of one​ donut? What is the cost of one large​ coffee?
Answer by Boreal(15235) About Me  (Show Source):
You can put this solution on YOUR website!
6D+2C=5.94; so 12D+4C=11.88
4D+5C=7.04; so -12D-15C=-21.12 multiplying by -3
-11C=-9.24, adding the two
C=$0.84
therefore 6D+1.68=5.94, so 6D=$4.26 and D=$0.71
check in second
4(0.71)+5(0.84)=$7.04
coffee is $0.84 and donut is $0.71