Question

A car travels along a motorway and the amount of petrol in its tank is monitored as shown on the graph on the next page. a) How much petrol was bought at the first stop? b) What was the petrol consumption in km per litre: i) before the first stop ii) between the two stops? c) What was the average petrol consumption over the 200 km?After it leaves the second service station the car is stuck in slow traffic for the next 20 km. Its petrol consumption is reduced to 4 km per litre. After that, the road clears and the car travels a further 75 km during which time the consumption is 7.5 km/litre Draw the graph above and extend it to show the next 95 km. How much petrol is in the tank at the end of the journey?​

Answer 1

Answer: a) 30 litres

b) i) 8 km/l ii) 6km/l

c) 20/3 km/ltr

b) i) points are (0,15) and (80,5)

consumption = (15-5)/(0-80) = 8 km/l

ii) points are (80,35) and (200,15)

consumptions = (200-80)/(15-35) = 6 km/l

c) Avg consumption = total km/total litres

= 200/(10+20)

= 20/3 km/l

Explanation: