2.5 meters equals 28.30 and you need 18 meters. First you need to divide 18 by 2.5 to understand the extra length you need to pay for. 18 divided by 2.5 equals 7.2. Now that you have that you multiply 28.30 by 7.2 because you are trying to figure out the amount it will cost. 28.30 times 7.2 equals $203.76.