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.

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:

\( \frac{8 + 6 + 10 + 4}{4} \) = \( \frac{28}{4} \) = 7

The distributive property for multiplication helps in solving expressions like a(b + c). It specifies that the result of multiplying one number by the sum or difference of two numbers can be obtained by multiplying each number individually and then totaling the results: a(b + c) = ab + ac. For example, 4(10-5) = (4 x 10) - (4 x 5) = 40 - 20 = 20.

If 39% of the town's 49,000 voters cast ballots the number of votes cast is:

(\( \frac{39}{100} \)) x 49,000 = \( \frac{1,911,000}{100} \) = 19,110

The mayor got 90% of the votes cast which is:

(\( \frac{90}{100} \)) x 19,110 = \( \frac{1,719,900}{100} \) = 17,199 votes.