Question: A class has 30 students. If the average score of the class is 75 and the average score of the top 10 students is 90, what is the average score of the bottom 20 students?
Options:
Correct Answer: 60
Solution:
Total score of 30 students = 30 * 75 = 2250. Total score of top 10 students = 10 * 90 = 900. Total score of bottom 20 students = 2250 - 900 = 1350. Average score of bottom 20 = 1350 / 20 = 67.5.
