Question 342315
let the bill be $x
sales tax = 5 % 
.

The bill with sales tax will be 1.05 x
...
15% tip on this value 
= 1.15 * 1.05x 
=1.2075x
1.2075x=90
x=90/1.2075
x $ 74.54
The bill should not be more than $ 74.53
..