How big of a cake pan do you need for about40 people?

For 40 people, you will need a cake pan that is approximately 18 inches by 13 inches. This pan size is commonly referred to as a half-sheet pan or a jelly-roll pan. It provides enough surface area to create a cake that can be easily sliced and served to a large group.

Here's a general guide to cake pan sizes based on the number of people you're serving:

- 6-inch pan: 6-8 people

- 8-inch pan: 12-16 people

- 9-inch pan: 20-24 people

- 12-inch pan: 30-36 people

- 18x13 inch pan (Half-sheet pan): 36-48 people

Keep in mind that cake pan sizes can vary slightly among brands and manufacturers, so it's always a good idea to check the dimensions of the pan before making your cake. Additionally, the thickness and height of the cake you're making may affect the number of servings it yields.