Step 1: Analyze Statement 1.
Statement 1 tells us that 30 percent of people who bought donuts also bought pizzas, but this doesn't give us the total number of people who bought donuts or pizzas. We don't know how many people bought donuts or how many bought pizzas, so statement 1 alone is insufficient.
Step 2: Analyze Statement 2.
Statement 2 tells us that 40 percent of people who bought pizzas also bought donuts, but again, we do not know the total number of people who bought either donuts or pizzas. Therefore, statement 2 alone is also insufficient.
Step 3: Combine Both Statements.
Combining both statements, we still don't know the total numbers of people who bought donuts or pizzas. Thus, we cannot determine if the number of people who bought donuts is greater than the number of people who bought pizzas.
Step 4: Conclusion.
The correct answer is (E).