Answer:
4 additional days.
Step-by-step explanation:
So the total charge is $575.
It costs $355 for 1 week of use of the van.
1 week is 7 days.
It costs $55 for each extra day of use of the van.
575=55d+355
d is for the unknown extra amount of days.
subtract 355 from both sides
220=55d
divide by 55 on both sides
4=d
So, the Dakotas used the van for 4 additional days. So in total the used the van for 4+7 days.
4+7=11 total days.
But the answer to the question is 4 days, because it specifically ask for additional days.