I have the answers for the first three but confused on number four (practice assessment)

If "x" is the rental fee, and the total taxes collected is 0.07x, the if the rental fee is:
[tex]\text{0}.07\times220=15.4[/tex]Therefore, she collects $15.4 in taxes.
the total amount in tax and gratuity is:
[tex]15.4+35=50.4[/tex]Therefore, in taxes and gratuity the total amount is $50.4