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.

To find the average of these 4 numbers add them together then divide by 4:

\( \frac{13 + 9 + 13 + 9}{4} \) = \( \frac{44}{4} \) = 11

To add these radicals together their radicands must be the same:

6\( \sqrt{12} \) + 5\( \sqrt{3} \)
6\( \sqrt{4 \times 3} \) + 5\( \sqrt{3} \)
6\( \sqrt{2^2 \times 3} \) + 5\( \sqrt{3} \)
(6)(2)\( \sqrt{3} \) + 5\( \sqrt{3} \)
12\( \sqrt{3} \) + 5\( \sqrt{3} \)

Now that the radicands are identical, you can add them together:

To divide terms with exponents, the base of both exponents must be the same. In this case they are so divide the coefficients and subtract the exponents:

\( \frac{9y^6}{2y^4} \)
\( \frac{9}{2} \) y^{(6 - 4)}
4\(\frac{1}{2}\)y²

Average speed in miles per hour is the number of miles traveled divided by the number of hours: