on average petrol used per km in australia?

Depends on your car. My little car takes 10 cents per km while our ute takes more than double of that. The average would probably be 20 cents a km. Not sure about prices in Perth, they're likely to be a bit more expensive than in the eastern states of Australia.
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My car uses 9 litres per 100km and is a 2.0 litre 4WD and I guess that's about average for a smallish to medium size car.

According to MotorMouth, the average price is Perth at the moment is around 113c per litre.
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little cars use less and larger, family cars use more. i have a toyota corolla and it costs me $30 – $40 to fill up and i'd get 400 – 500k's out of it.
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For what type of car ???? Need more info mate.
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