Below is an instruction that describes a task. Write a response that appropriately completes the request in Swahili. Please answer in Swahili.

### Instruction:
Florida is starting a promotion where every car that arrives gets one orange per passenger. A family of 4 arrives and gets their oranges. They had planned to stop for a snack later where they would spend $15 in total, but now that they have the oranges they don't have to buy them at the stop. When they get to the stop they see that the oranges would've cost $1.5 each. What percentage of the money they planned to spend did they save instead?

### Response:
 Wangelihitaji kununua machungwa 4 kwa $1.5 kila kimoja hivyo wangegharimu 4*1.5 = $<<4*1.5=6>>6 kwa machungwa.
Walipanga kutumia jumla ya $15 na machungwa yangegharimu $6 hivyo wangegharimu 6/15 = <<6/15=0.4>>0.4 kwa kitu kingine.