SOLUTION: Mrs. Neil bought $155 in groceries. She paid her bill in$5 and$20 notes using a total of 13 notes. Calculate how many $20 notes were used.

Algebra ->  Coordinate Systems and Linear Equations  -> Linear Equations and Systems Word Problems -> SOLUTION: Mrs. Neil bought $155 in groceries. She paid her bill in$5 and$20 notes using a total of 13 notes. Calculate how many $20 notes were used.       Log On


   

Question 819984: Mrs. Neil bought $155 in groceries. She paid her bill in$5 and$20 notes using a total of 13 notes. Calculate how many $20 notes were used.
Answer by TimothyLamb(4379) About Me  (Show Source):
You can put this solution on YOUR website!
5f + 20t = 155
f + t = 13
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solve the above system of linear equations for f and t:
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answer:
f = 7
t = 6
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