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CEMC Pascal, 2026

Algebra Difficulty 1.5 Junior Find the answer Canada

Peter’s car uses 10.210.2 L of
fuel per 100100 km. Mike’s hybrid car
uses 6.66.6 L of fuel per 100100 km. Fuel costs $1.40\$1.40 per litre. If both Peter and Mike
drive 200200 km, how much less does
Mike spend on fuel?

Pick one

Solution

Peter’s car uses 10.2 L10.2 \text{ L} of fuel per 100 km100 \text{ km}, and thus uses 2×10.2 L=20.4 L2\times10.2\text{ L}=20.4 \text{ L} of
fuel per 200 km200 \text{ km}. Fuel costs
$1.40/L\$1.40/\text{L} and so Peter spends
$1.40/L×20.4 L=$28.56\$1.40/\text{L}\times20.4\text{ L}=\$28.56 on fuel.

Mike’s car uses 6.6 L6.6 \text{ L} of
fuel per 100 km100 \text{ km}, and thus
uses 2×6.6 L=13.2 L2\times6.6\text{ L}=13.2\text{ L} of fuel per 200 km200 \text{ km}. Fuel costs $1.40/L\$1.40/\text{L} and so Mike spends $1.40/L×13.2 L=$18.48\$1.40/\text{L}\times13.2\text{ L}=\$18.48 on fuel.

Mike spends $28.56−$18.48=$10.08\$28.56-\$18.48=\$10.08
less than Peter on fuel.

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