A car owner buys petrol at ₹ 40, ₹ 50 and ₹ 60 per litre for 3 consecutive years. If he spends ₹ 30,000 each year, what is the average cost of a litre of petrol? (correct to two decimal places)
- A₹ 48.65
- B₹ 51.20
- C₹ 49.20
- D₹ 50
Solution & Step-by-step Explanation
Amount spent each year = ₹ 30,000.
Quantity of petrol bought in the 1st year:
Q
1
=
40
30000
=750 litres
Quantity of petrol bought in the 2nd year:
Q
2
=
50
30000
=600 litres
Quantity of petrol bought in the 3rd year:
Q
3
=
60
30000
=500 litres
Total quantity of petrol bought over 3 years:
Total Quantity=750+600+500=1850 litres
Total amount spent over 3 years:
Total Amount=30000+30000+30000=₹ 90,000
Average cost per litre:
Average Cost=
Total Quantity
Total Amount
=
1850
90000
≈₹ 48.648
Rounding off to two decimal places gives ₹ 48.65.
Quantity of petrol bought in the 1st year:
Q
1
=
40
30000
=750 litres
Quantity of petrol bought in the 2nd year:
Q
2
=
50
30000
=600 litres
Quantity of petrol bought in the 3rd year:
Q
3
=
60
30000
=500 litres
Total quantity of petrol bought over 3 years:
Total Quantity=750+600+500=1850 litres
Total amount spent over 3 years:
Total Amount=30000+30000+30000=₹ 90,000
Average cost per litre:
Average Cost=
Total Quantity
Total Amount
=
1850
90000
≈₹ 48.648
Rounding off to two decimal places gives ₹ 48.65.