Class 10, consisting of 40 students, took a science test. 30 students had an average score of 95. The other students had an average score of 85. What is the average score of the whole class?
Show answer & explanation
Correct answer: B
Explanation
The correct answer is Option 2 i.e. 92.5.
Average = Sum of observations/Number of observations
According to the question,
An average of 30 students,
⇒ 95 = Total Sum/30
⇒ Sum = 95 × 30 = 2850
Average of the rest of the 10 students,
⇒ 85 = Sum/10
⇒ Sum = 850
Now the new average,
⇒ Average = (2850 + 850)/40
⇒ Average = 3700/40 = 92.5