You would spend $71.32 per week on gas.
Step 1. Convert weeks to days
Time = 1 wk × (7 days/1 wk) = 7 days
Step 2. Calculate the distance travelled
Distance = 7days × 125 km/day = 875 km
Step 3. Convert kilometres to miles
Distance = 875 km × (1 mi/1.609 km) = 543.8 mi
Step 4. Calculate the gallons of gas
V = 543.8 mi × (1 gal/40.0 mi) = 13.60 gal
Step 5. Convert gallons to litres
V = 13.60 US gal × (3.785 L/1 US gal) = 51.46 L
Step 6. Calculate the cost of the gas
Cost = 51.46 L × (€1.10/1 L) = €56.60
Step 7. Convert euros to dollars
Cost = €56.60 × ($1.26/€1) = $71.32