The size of a cake is generally inches, 1 inch ≈2.54cm, and we usually use pounds to express the weight of the cake, 1 pound ≈453 grams. How to buy a cake, avoiding waste and not being stingy? There is such a simple formula:

6 inches, diameter ≈ 15cm, 1 kg, 1-3 people to eat;

8 inches, diameter ≈ 18cm, 2 kg, 3-5 people to eat;

10 inch, diameter ≈25cm, 3 kg, 5-8 people eat;

12 inch, diameter ≈30cm, 4 kg, 8- 10 people eat;

A catty is about 453 grams, so a cake of 280 grams is about half a catty, so it is not big.