So for this question we need to consider two different thing, the cost of the car hire and the cost of petroleum. Taking the cost of the car hire first, the car costs 99.4 CHF per day, if we hired the car for four days, the total cost will be: 4 x 99.4 = 397.6CHF now for the cost of petrol, if the car uses 0.08l of petrol for every km it drives, it will use a total of: 0.08 x 525 = 42l of petrol If petrol costs 1.35CHF per litre then the total petrol cost is: 42 x 1.35 = 56.7CHF adding these all together you get: 56.7 + 397.6 = 454.3CHF Hope this helps!