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

4c² x c⁷
(4 x 1)c^{(2 + 7)}
4c⁹

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 add these radicals together their radicands must be the same:

3\( \sqrt{80} \) + 4\( \sqrt{5} \)
3\( \sqrt{16 \times 5} \) + 4\( \sqrt{5} \)
3\( \sqrt{4^2 \times 5} \) + 4\( \sqrt{5} \)
(3)(4)\( \sqrt{5} \) + 4\( \sqrt{5} \)
12\( \sqrt{5} \) + 4\( \sqrt{5} \)

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

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

\( \frac{16 + 12 + 16 + 12}{4} \) = \( \frac{56}{4} \) = 14

The amount of flour you need is (3\(\frac{1}{4}\) - \(\frac{5}{8}\)) cups. Rewrite the quantities so they share a common denominator and subtract:

(\( \frac{26}{8} \) - \( \frac{5}{8} \)) cups
\( \frac{21}{8} \) cups
2\(\frac{5}{8}\) cups