A rational number (or fraction) is represented as a ratio between two integers, a and b, and has the form \({a \over b}\) where a is the numerator and b is the denominator. An improper fraction (\({5 \over 3} \)) has a numerator with a greater absolute value than the denominator and can be converted into a mixed number (\(1 {2 \over 3} \)) which has a whole number part and a fractional part.

If 84% of the town's 19,000 voters cast ballots the number of votes cast is:

(\( \frac{84}{100} \)) x 19,000 = \( \frac{1,596,000}{100} \) = 15,960

The mayor got 79% of the votes cast which is:

(\( \frac{79}{100} \)) x 15,960 = \( \frac{1,260,840}{100} \) = 12,608 votes.

To divide fractions, invert the second fraction and then multiply:

\( \frac{3}{9} \) ÷ \( \frac{1}{7} \) = \( \frac{3}{9} \) x \( \frac{7}{1} \)

To multiply fractions, multiply the numerators together and then multiply the denominators together:

\( \frac{3}{9} \) x \( \frac{7}{1} \) = \( \frac{3 x 7}{9 x 1} \) = \( \frac{21}{9} \) = 2\(\frac{1}{3}\)

A factorial has the form n! and is the product of the integer (n) and all the positive integers below it. For example, 5! = 5 x 4 x 3 x 2 x 1 = 120.

To simplify a radical, factor out the perfect squares:

\( \sqrt{45} \)
\( \sqrt{9 \times 5} \)
\( \sqrt{3^2 \times 5} \)
3\( \sqrt{5} \)