Tony Firshman writes: >>Monetary calculations normally only require the four basic >>operations, add, subtract, multiply and divide.
>Surely two only - addition and subtraction? >Multiplication and division are shorthand for >addition/subtraction in my book. > >... or am I being too simplistic. It all depends on what youre trying to do. Working out percentages requires the use of multiplication and division, for example, and as someone pointed out, you'll need powers to calculate compound interest rates. Theres no limit. Look at large companies, such as the late Enron, they even use imaginary numbers! However, nowadays, subtraction seems to be all the rage. As you point out in a later mail, most of these operations are merely addition or subtraction at heart. I once had an old mechanical calculating machine, given to me by my grandfather to play with when the bank he worked for upgraded to electro-mechanical ones. I later used it for my homework, the only kid at school with access to a calculator, (something I had to keep secret as my teacher would not have approved.) Division was quite a convoluted affair involving multiple subtractions and shifts. I used that same algorithm later in my assembler longword division routine. Per
