Answer: [tex]\$(23.65+1.343s)[/tex]
Step-by-step explanation:
Given
Speaker set to cost $22
Each song costs $1.25
Sales tax is 7.5%
Suppose, one purchase s no of songs
The cost of s songs is $1.25s
The combined cost of speakers and song is
[tex]C=22+1.25s[/tex]
At this cost, a 7.5% sales tax is applied to the given cost
[tex]\Rightarrow [22+1.25s]\times 0.075[/tex]
Total cost after sales tax is
[tex]\Rightarrow C_t=22+1.25s+[22+1.25s]0.075\\\\\Rightarrow C_t=[22+1.25s](1+0.075)=[22+1.25s]\times 1.075\\\\\Rightarrow C_t=\$(23.65+1.343s)[/tex]