The first few multiples of 4 are [4, 8, 12, 16, 20, 24, 28, 32, 36, 40] and the first few multiples of 12 are [12, 24, 36, 48, 60, 72, 84, 96]. The first few multiples they share are [12, 24, 36, 48, 60] making 12 the smallest multiple 4 and 12 have in common.

To convert a negative exponent to a positive exponent, calculate the positive exponent then take the reciprocal.

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.

Calculate the number of vans needed by dividing the number of people that need transported by the capacity of one van:

vans = \( \frac{63}{10} \) = 6\(\frac{3}{10}\)

So, it will take 6 full vans and one partially full van to transport the entire team making a total of 7 vans.

The amount of flour you need is (3\(\frac{1}{2}\) - 1\(\frac{1}{2}\)) cups. Rewrite the quantities so they share a common denominator and subtract:

(\( \frac{28}{8} \) - \( \frac{12}{8} \)) cups
\( \frac{16}{8} \) cups
2 cups