Gli bought 9 cds.some of them cost $12.75, and the rest cost $11.95. the total was $112.35. how many did he buy at each price?
Let E be the expensive, and C the cheaper.
E+C=9
E(12.75) + C (11.95)=112.35
the answer to your math problem is 6 cds for 12.75 and 3 cds for 11.95
To solve this problem, we can set up a system of linear equations.
Let E represent the number of CDs that were purchased at the expensive price of $12.75, and let C represent the number of CDs that were purchased at the cheaper price of $11.95.
We know that the total number of CDs purchased is 9, so we can write the equation E + C = 9.
We also know that the total cost of the CDs is $112.35, so we can write the equation 12.75E + 11.95C = 112.35.
To solve this system of equations, we can use substitution or elimination. In this case, let's use substitution.
From the first equation, we can solve for E:
E = 9 - C
Substituting this into the second equation, we get:
12.75(9 - C) + 11.95C = 112.35
Distributing and simplifying, we have:
114.75 - 12.75C + 11.95C = 112.35
Combining like terms, we get:
-0.8C = -2.4
Dividing both sides by -0.8, we find:
C = 3
Substituting this value of C back into the first equation, we get:
E + 3 = 9
E = 6
Therefore, Gli bought 6 CDs at $12.75 each and 3 CDs at $11.95 each.