Question

One group of 40 students has a mean score 75in exam.A second group of 50 students has a mean score of 60.A third group of 30 students has a mean score of 85.Find the mean of all 120 stidents

Answer 1

Answer:73

Explanation:

add 75 + 60 + 85 = 220

then divide to divide you need to find how much times you added then divide by 220 so 75 + 60 + 85 which is 3 times so you divide 220 by 3 and you get 73.33333333333333 or 73