Question

a class of 30 students took the final exam in social studies. 12 of the students had a score of 70 points. the remaining students had an average score of 80. what is the average score of the entire class?
71 points
76 points
79 points
78 points
75 points

Explanation:

Step1: Find the number of remaining students

Total students are 30, and 12 have a score of 70. So remaining students = \( 30 - 12 = 18 \)

Step2: Calculate total score of 12 students

Score of 12 students with 70 each: \( 12 \times 70 = 840 \)

Step3: Calculate total score of 18 students

Score of 18 students with average 80: \( 18 \times 80 = 1440 \)

Step4: Calculate total score of the class

Total score = \( 840 + 1440 = 2280 \)

Step5: Calculate average score of the class

Average score = \( \frac{2280}{30} = 76 \)

Answer:

76 points