The number of students taking German or Spanish is 12 + 8 = 20. Of that group of 20, 4 are taking both languages so they've been counted twice (once in the German group and once in the Spanish group). Subtracting them out leaves 20 - 4 = 16 who are taking at least one language. 27 - 16 = 11 students who are not taking either language.

To add these distances, they must share the same unit so first you need to first convert the swim distance from meters (m) to kilometers (km) before adding it to the bike and run distances which are already in km. To convert 100 meters to kilometers, divide the distance by 1000 to get 0.1km then add the remaining distances:

total distance = swim + bike + run
total distance = 0.1km + 50.7km + 15.3km
total distance = 66.1km

To divide terms with exponents, the base of both exponents must be the same. In this case they are so divide the coefficients and subtract the exponents:

\( \frac{-5b^7}{7b^4} \)
\( \frac{-5}{7} \) b^{(7 - 4)}
-\(\frac{5}{7}\)b³

To add or subtract terms with exponents, both the base and the exponent must be the same. In this case they are so subtract the coefficients and retain the base and exponent:

8c² - 4c²
(8 - 4)c²
4c²

To add these radicals together their radicands must be the same:

2\( \sqrt{80} \) + 8\( \sqrt{5} \)
2\( \sqrt{16 \times 5} \) + 8\( \sqrt{5} \)
2\( \sqrt{4^2 \times 5} \) + 8\( \sqrt{5} \)
(2)(4)\( \sqrt{5} \) + 8\( \sqrt{5} \)
8\( \sqrt{5} \) + 8\( \sqrt{5} \)

Now that the radicands are identical, you can add them together: