Question

1. One week Carlos bought 3 bags of Tabitha Tidbits and 4 bags of Figaro Flakes for $43.00. The next week he bought 3 bags of Tabitha Tidbits and 6 bags of Figaro Flakes for $54.00. Based on this information, figure out the price of one bag of each type of cat food. Explain your reasoning.

Answer 1

Tabitha Tidbits costs $7 per bag, and Figaro Flakes is $5.50 per bag.
You need to set up a system of equations. Use "x" for Tabitha Tidbits and "y" for Figaro Flakes, and let the total cost of each trip equal c. Using the equation ax+by=c, substitute the cost of each trip in for c, and the number of bags for each food for a and b respectively. The two equations will be:
3x+4y=43
3x+6y=54
Isolate x in the first equation and you will get:
x=(43-4y)/3
Substitute the above equation for x into the other equation:
3*((43-4y)/3)+6y=54
Isolate y in this equation, and you will get 11/2, which is 5.5
So the cost of one bag of Figaro Flakes is $5.50
Now substitute this into the equation where you isolated x:
(43-4(5.5))/3
You will get x=7, so a bag of Tabitha Tidbits is $7