A salesperson with a three-product line calls on 200 customers over a period of time. These 200 customers place orders as follows:
100 ordered product A
95 ordered product B
85 ordered product C
50 ordered products A and B
55 ordered products A and C
30 ordered products B and C
20 ordered products A, B, and C
Determine the number of customers who order: (a) at least one product, (b) no products, (c) exactly one product, (d) exactly two products, (e) exactly three products.
Use a venn diagram to illustrate...
The Attempt at a Solution
I drew a venn diagram showing the overlaps in the product purchases. I also took the ratios between the number of products to the customers, e.g. [tex] 100/200, 95/200, 85/200[/tex] etc. But I have no idea how to apply these to get the answers. I just guessed that those ratios would be significant somehow. This comes from a worksheet, but the textbook is only covering set theory. We haven't discussed this in class either, so I'm stuck.