As we can see from the first column, for 2 cakes, 8 eggs are needed. That is, the ratio is 2:8.
This same ratio can be simplified to 1:4, that is, if you need 8 eggs for 2 cakes, you only need hafl as many for 1 cake.
If we mantain this ratio for the 7 cakes, this means that we will need 4*7 eggs:
28 eggs are needed to make 7 cakes.