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

Solving for distance:

distance = \( \text{speed} \times \text{time} \)
distance = \( 55mph \times 9h \)
495 miles

The amount of flour you need is (2\(\frac{5}{8}\) - 1\(\frac{1}{8}\)) cups. Rewrite the quantities so they share a common denominator and subtract:

(\( \frac{21}{8} \) - \( \frac{9}{8} \)) cups
\( \frac{12}{8} \) cups
1\(\frac{1}{2}\) cups

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

\( \frac{1}{9} \) x \( \frac{2}{5} \) = \( \frac{1 x 2}{9 x 5} \) = \( \frac{2}{45} \) = \(\frac{2}{45}\)

To simplify this fraction, first find the greatest common factor between them. The factors of 40 are [1, 2, 4, 5, 8, 10, 20, 40] and the factors of 76 are [1, 2, 4, 19, 38, 76]. They share 3 factors [1, 2, 4] making 4 their greatest common factor (GCF).

Next, divide both numerator and denominator by the GCF:

\( \frac{40}{76} \) = \( \frac{\frac{40}{4}}{\frac{76}{4}} \) = \( \frac{10}{19} \)

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.