Petrol Prices
Weekly Problem 28 - 2009
How much does $u$ litres of unleaded cost in terms of the cost per litre of 4 star petrol?
How much does $u$ litres of unleaded cost in terms of the cost per litre of 4 star petrol?
Age
11 to 14
Challenge level
Problem
Diesel at $s$ pence per litre costs 3 pence per litre more than unleaded. How many pence does it cost to buy $u$ litres of unleaded petrol?
If you liked this problem, here is an NRICH task which challenges you to use similar mathematical ideas.
Student Solutions
$u(s-3)$.
Unleaded costs $s-3$ pence per litre, so $u$ litres of unleaded costs $u(s-3)$.