Given below is a population chart regarding different ages. Read it carefully and answer the questions.
Age
group Frequency
01-10 5000
11-20 6254
21-30 10000
31-40 1235
41-50 9800
51-60 6500
a) Calculate the average age of the population.
b) What is the class interval and which interval has the highest weight?
(b) just look to see which has the highest weight
(a) to find the average age, it's not exactly straightforward, since we do not know how the ages are distributed in each class. But, assuming that each class's average age is the average of the range, then the weighted average age of the whole group is
(5*5000 + 15*6254 + ... + 45*9800 + 55*6500)
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(5000 + 6254 + ... + 9800 + 6500)