Give the step-by-step reasoning process and then the final answer. Julia has a parrot and a rabbit. She buys food for both of the animals for $30 in total a week. Julia has the rabbit for 5 weeks, and the parrot for 3 weeks. How much money did Julia already spend on food for her animals, if the weekly cost of the rabbit food is $12?
If the rabbit food costs $12 a week, then the parrot food costs $30 - $12 = $18 a week. Julia has the parrot for 3 weeks, so she spent 3 weeks * $18 / week = $54 on her. The rabbit is her only for 5 weeks, so she spent 5 weeks * $12 / week = $60 on him. In total, Julia spent $54 + $60 = $114 on food for her animals.
The final answer: 114.