Consider the following grouped frequency distribution: x f 0-10 8 10-20 12 20-30 10 30-40 p 40-50 9 If the mean of the above data is 25.2, then what is the value of p?
Correct Answer: 11
Explanation:
Mean = (sum of fixi/ (sum of f) = (8*5 + 12*15 + 10*25 + P*35 +9*45) / (8+12+10+P+9) = 25.2
