Answer: 385 dollars
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Work Shown:
(220 dollars)/(4 days) = (x dollars)/(7 days)
220/4 = x/7
220*7 = 4*x
1540 = 4x
4x = 1540
x = 1540/4
x = 385
It costs $385 to rent a car for a full week (7 days)
If your teacher considers a week to be 5 days (ignoring the weekends), then you'll need to solve 220/4 = x/5 instead. That would lead to x = 275. I have a feeling that your teacher might want 7 days though.
Side note: In the jump from step 2 to step 3, I used the cross multiplication rule.
