A trader bought some paraffin for $500. He paid $x for each litre of paraffin. (a) Find, in term of x, an expression for the number of litres he bought.
(b) Due to a leak, he lost 3 litres of paraffin. He sold the remainder of the paraffin for $1 per litre more than he paid for it.
Write down an expression, in term of x, for the sum of money he received.
(c) He made a profit of $20.
(i) Write down an equation in x to represent this information, and show that it reduces to 3x²+ 23x – 500 = 0.
(ii) Solve the equation 3x² + 23x – 500 = 0, giving both answers correct to one decimal place.
(d)Find, correct to the nearest whole number, the number of litres of paraffin he sold.