Question 188977
let x be the number of days
:
cost of PC=30x+15
cost of  F=28x+27
:
30x+15=28x+27
:
2x=12
:
x=6 days......cost would be 30(6)+15=$195
:
if this was for 7 days cost of PC=30(7)+15=225
                       cost of F=28(7)+27=223
:
so Fido's has the cheaper cost for 7 days........