Christine scored 80% on the test meaning she earned 80% of the possible points on the test. There were 160 possible points on the test so she earned 160 x 0.8 = 128 points. Each question is worth 2 points so she got \( \frac{128}{2} \) = 64 questions right.

A factor is a positive integer that divides evenly into a given number. For example, the factors of 8 are 1, 2, 4, and 8.

To add these fractions, first find the lowest common multiple of their denominators. 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 share.

Next, convert the fractions so each denominator equals the lowest common multiple:

\( \frac{2 x 3}{4 x 3} \) + \( \frac{7 x 1}{12 x 1} \)

\( \frac{6}{12} \) + \( \frac{7}{12} \)

Now, because the fractions share a common denominator, you can add them:

\( \frac{6 + 7}{12} \) = \( \frac{13}{12} \) = 1\(\frac{1}{12}\)

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

vans = \( \frac{91}{15} \) = 6\(\frac{1}{15}\)

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

To find the average of these 4 numbers add them together then divide by 4:

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