Peter’s car uses 10.2 L of fuel per 100 km. Mike’s hybrid car uses 6.6 L of fuel per 100 km. Fuel costs $1.40 per litre. If both Peter and Mike drive 200 km, how much less does Mike spend on fuel?
Pick one
Solution
Peter’s car uses 10.2 L of fuel per 100 km, and thus uses 2×10.2 L=20.4 L of fuel per 200 km. Fuel costs $1.40/L and so Peter spends $1.40/L×20.4 L=$28.56 on fuel.
Mike’s car uses 6.6 L of fuel per 100 km, and thus uses 2×6.6 L=13.2 L of fuel per 200 km. Fuel costs $1.40/L and so Mike spends $1.40/L×13.2 L=$18.48 on fuel.
Mike spends $28.56−$18.48=$10.08 less than Peter on fuel.
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