Mean Net Income Calculation | CFA Level 1 Exam Preparation

Mean Net Income

Prev Question Next Question

Question

The net incomes of a sample of importers were organized into the following table:

Net Income (in $ millions) Number of Importers

2 - 41

5 - 74

8 - 1010

11 - 133

14 - 162

What is the mean net income?

Answers

Explanations

Click on the arrows to vote for the correct answer

A. B. C. D. E.

D

(3*1)+(6*4)+(9*10)+(12*3)+(15*2) = 183. Mean is 183/20 = 9.15

To find the mean net income, we need to calculate the average of the net incomes provided in the table.

First, we can calculate the midpoint for each interval by taking the average of the lower and upper bounds. Then, we multiply each midpoint by its corresponding frequency (number of importers) to get the total income for each interval. Finally, we sum up all the total incomes and divide by the total number of importers to obtain the mean net income.

Let's calculate it step by step:

Lower Bound (in $ millions) | Upper Bound (in $ millions) | Midpoint (in $ millions) | Frequency | Total Income (Midpoint * Frequency)

2 | 4 | 3 | 41 | 3 * 41 = 123 5 | 7 | 6 | 74 | 6 * 74 = 444 8 | 10 | 9 | 1010 | 9 * 1010 = 9090 11 | 13 | 12 | 133 | 12 * 133 = 1596 14 | 16 | 15 | 162 | 15 * 162 = 2430

Now, we sum up all the total incomes: Total Income = 123 + 444 + 9090 + 1596 + 2430 = 13683

Next, we sum up all the frequencies to find the total number of importers: Total Importers = 41 + 74 + 1010 + 133 + 162 = 1420

Finally, we can calculate the mean net income by dividing the total income by the total number of importers: Mean Net Income = Total Income / Total Importers = 13683 / 1420 ≈ $9.6338 million

Rounded to the nearest million, the mean net income is approximately $9.00 million.

Therefore, the correct answer is E. $9.00 million.