A group of 120 people were asked whether their income level is above or below $25,000 and whether they subscribe to a movie chan
nel. The data from the survey is shown in the Venn diagram. Use the Venn diagram to find the missing values in the frequency table. Which shows the correct values for the variables in the table?
A: a = 18, b = 34, c = 65 B: a = 34, b = 18, c = 68 C: a = 34, b = 68, c = 47 D: a = 47, b = 18, c = 68
The answer is B. Taking a look at the diagram, we see that there are 18 people in the overlap section, where people are both subscribers and below 25000. Hence b = 34. There are 34 people in the right-hand section, where they are subscribers but have an income that is not below 25000 (I.e. Above 25000). Hence a = 34. Finally, c is just the total of that row, so 55 + 13 = 68 = c.