Answer:
The sweater costs 10 dollars.
Step-by-step explanation:
We can use proportion to solve this:
[tex] \frac{125 \: dollars}{4250 \: pesos} = \frac{x}{340 \: pesos} \\ \\ \frac{4250x}{4250} = \frac{42500}{4250} \\ \\ x = 10 \\ x = 10 \: dollars[/tex]
