Answer:
C. 8
Explanation:
One way to solve this is to find 30% of each class, 28 and 24.
30% of 28:
28 • 0.30 = 8.4
30% of 24:
24 • 0.30 = 7.2
You can then find the average of these two numbers.
8.4 + 7.2 = 15.6
15.6 ➗ 2 = 7.8
7.8 rounds up to 8
Another way to solve is to first find the average number of people in each class.
28 + 24 = 52
52 ➗ 2 = 26
You can then find 30% of this number.
26 • 0.30 = 7.8
7.8 rounds up to 8
For this case we must do a conversion. By definition we have to:
1 milligram equals 1000 micrograms
1 liter equals 1000 milliliters
So:

Answer:
