2.5 times the cost of 3 songs on Itunes decreased by $1.30 will give you the cost of 7 songs. If 7 songs will cost you $18.30, how much will 3 songs cost?

Answer 1

We are solving for the cost of songs in this problem, and there are two separate equations being described. To represent the cost of one song, we will use the variable "c" in both equations.

These are the equations:

2.5 x (3c) - 1.30 = 7c

7c = 18.30

Since both equations are equal to 7 times the cost of one song (c), you can equal the equations to each other:

2.5 x (3c) - 1.30 = 18.30

And now you solve for 3c.

2.5(3c) = 18.30 - 1.30

2.5(3c) = 17.00

3c = 17.00/2.5

3c = 6.8

Be careful with solving for c, because the question asks for the cost of 3 songs (3c). Therefore, the cost of three songs is $6.80.