*Takes the number of extra ingredients

*Works out the selling cost of the pizza from the above information

sellingcost = cost * 1.5
cost = fixedcost + (basecost*area) + (number of extra ingredients*extracost*area)
area = pi * r^2
basecost=cost of the base per metre squared
extracost=cost of an extra ingredient per metre squared
fixedcost=the fixed cost involved in making the pizza ie. labour