The absolute value is the positive magnitude of a particular number or variable and is indicated by two vertical lines: \(\left|-5\right| = 5\). In the case of a variable absolute value (\(\left|a\right| = 5\)) the value of a can be either positive or negative (a = -5 or a = 5).

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

6\( \sqrt{27} \) - 5\( \sqrt{3} \)
6\( \sqrt{9 \times 3} \) - 5\( \sqrt{3} \)
6\( \sqrt{3^2 \times 3} \) - 5\( \sqrt{3} \)
(6)(3)\( \sqrt{3} \) - 5\( \sqrt{3} \)
18\( \sqrt{3} \) - 5\( \sqrt{3} \)

Now that the radicands are identical, you can subtract them:

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.

The least common multiple (LCM) is the smallest positive integer that is a multiple of two or more integers.

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

\( \frac{17 + 11 + 18 + 10}{4} \) = \( \frac{56}{4} \) = 14