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

\( \frac{1}{9} \) ÷ \( \frac{4}{7} \) = \( \frac{1}{9} \) x \( \frac{7}{4} \)

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

\( \frac{1}{9} \) x \( \frac{7}{4} \) = \( \frac{1 x 7}{9 x 4} \) = \( \frac{7}{36} \) = \(\frac{7}{36}\)

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:

\( \frac{13 + 7 + 11 + 9}{4} \) = \( \frac{40}{4} \) = 10

The yearly interest charged on this loan is the annual interest rate multiplied by the amount borrowed:

interest = annual interest rate x loan amount

i = (\( \frac{6}{100} \)) x $100
i = 0.07 x $100
i = $7

To add or subtract terms with exponents, both the base and the exponent must be the same. In this case they are so subtract the coefficients and retain the base and exponent:

-7y⁶ - 1y⁶
(-7 - 1)y⁶
-8y⁶