A car owner buys petrol at 7.50, 8.00 and 8.50 per litre for three successive years. What approximately is his average cost per litre of petrol if he spends 4000 each year?	Choose the correct choice from the following answers:
A) 8	B) 9	C) 7.98	D) 8.50	E) None of these
Let average cost of petrol per litre be x   Then x = 12000 /4000/7.5+4000/8+4000/8.5   = 3 /2/15+1/8+2/17=6120/767= Rs. 7.98 per litre   Answer 7.98
<result>C</result>
A car owner buys petrol at 7.50, 8.00 and 8.50 per litre for three successive years. What approximately is his average cost per litre of petrol if he spends 4000 each year?