I don't know what you mean by monarchy, but monomial in math has 3 terms.
Catherine could take the original price of $144.97 and multiply it by .09 (9%). This would equal a sales tax of $13.073 which could be rounded to $13.01. Then add the original price of $144.97 to the tax of $13.01 to get a total of $157.98.
For me personally i can work nearly any equation with a calculator. definitely a good choice <span />
