I can't find anything on capacity for this size pan. 12x18x2 takes 14 cups, but that doesn't help you much. You can determine the pan capacity by pouring water, a cup at a time, about 2/3 of the way up the side of the pan. That will leave room for the cake to rise.
I would try about 2.. If that doesn't work, more.
3 cake box mixes for a 12 X 18 pan
2
18-inches
In a 12" x 17" pan? Don't do it, that will overflow. You can barely bake two boxes per sheet, it's nearly too much. As for the timing for two boxes, it's about 35-45 minutes at 325-350 degrees.
15 minutes keep looking at it from time to time just in case it has aready cooked thank you. 15 mins won't even bake a cupcake!! A 12 inch cake pan will probably take about 45-50 mins. Look for the cake pulling away from sides of pan. Also tap your finger in the middle of the cake. If it springs back, it is baked. If it dents in, continue to bake a bit longer and check again.
12 minutes and 30 seconds
How deep is the pan? 2" or 3"? It makes a huge difference.
To bake, fill, ice & decorate a wedding cake can take anywhere from 12 hours to many days to complete. It depends on how large it is, how many tiers it is comprised of, how detailed the icing/pattern is on the exterior, etc.
You can use two cake recipes for that size pan.
fOUR
Typically a cake in a 9 x 12 inch pan will take around 30-38 minutes to bake. Time will vary depending on the type of cake you are baking and how thick or dense the batter is. You can tell a cake is done baking by sticking a toothpick in the middle to see if it comes out clean of crumbs or with a small amount of crumbs. Also, you can tell if a cake is done baking if the edges of the cake are pulling away from the sides of the pan.
Your question is quite vague. However, I will try my best to answer it. You are most likely looking for the area of the inside surface of the pan. Assuming a diameter of twelve inches, the area of a circle would be ((12/2)^2)*pi (about 22/7) square inches, or about 113 square inches. If you mean that the circumference is twelve inches, then the area would be ((12/pi)/2)^2 * pi or about 11.459 square inches. Please double-click on the words "diameter" and "circumference" if you are unsure of which answer you need.
10-12 cups of batter
A muffin pan also known as a muffin tin is typically a metal pan usually with 12 cups or indentations used to bake muffins or cupcakes.
A 12" x 18" cake pan will make 72 servings.