Sure, let's solve this step-by-step.
1. Understand the given information:
- The cost of 15 litres of petrol is £12.
2. Determine the cost per litre of petrol:
- To find the cost per litre, divide the total cost by the number of litres.
[tex]\[
\text{Cost per litre} = \frac{£12}{15 \text{ litres}} = £0.8 \text{ per litre}
\][/tex]
3. Now, calculate the cost for 20 litres of petrol:
- Multiply the cost per litre by the number of litres you want to find the price for.
[tex]\[
\text{Cost for 20 litres} = £0.8 \text{ per litre} \times 20 \text{ litres} = £16
\][/tex]
So, the cost of 20 litres of petrol is £16.
