To fill a 10 gallon tank exactly halfway you'll need 5 gallons of fuel. Each fuel can holds 1 gallons so:

cans = \( \frac{5 \text{ gallons}}{1 \text{ gallons}} \) = 5

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 commutative property states that, when adding or multiplying numbers, the order in which they're added or multiplied does not matter. For example, 3 + 4 and 4 + 3 give the same result, as do 3 x 4 and 4 x 3.

To divide terms with radicals, divide the coefficients and radicands separately:

\( \frac{16\sqrt{21}}{8\sqrt{3}} \)
\( \frac{16}{8} \) \( \sqrt{\frac{21}{3}} \)
2 \( \sqrt{7} \)

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.