CEMC Cayley, 2003

Algebra Difficulty 2.0 Junior Find the answer Canada

A car uses 8.4 litres of gas for every 100 km it is driven. A mechanic is able to modify the car's engine at a cost of $400 so that it will only use 6.3 litres of gas per 100 km. The owner determines the minimum distance that she would have to drive to recover the cost of the modifications. If gas costs $0.80 per litre, this distance, in kilometres, is between

(A) $10\,000$ and $14\,000$ (B) $14\,000$ and $18\,000$ (C) $18\,000$ and $22\,000$ (D) $22\,000$ and $26\,000$ (E) $26\,000$ and $30\,000$

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