Zoe paid $18.60 in sales tax and tips for her dinner. The sales tax rate is 11% and she tipped 20%. (The sales tax does not apply to the tip, and the tip is based on the price of the dinner before sales tax.)
From the given hint, it is clear that both sales tax and tip apply on dinner price only. So we have:-
Sales Tax = 11% of dinner price
Tip = 20% of dinner price
And Sales Tax + Tip = $18.60
So (20+11)% of dinner price = 18.60
31% of dinner price = 18.60
0.31 * dinner price = 18.60
dinner price = 18.60/0.31 = 60
So Zoe's dinner price was $60.
