Optimum production plan

Just to make sure that they do not use more than the 12,000 grams available.

But we considered that and formed the optimum prod plan isnt it. we can straightaway go to profit isnt it ( 2.60 *5040 + 1.75* 1960 + 1*5000) – FC ( 3000)

But what you have written is not the profit - the correct profit is that shown in the answer!! You can multiplied the contribution per unit by the number of grams. You should be multiplying by the number of units. And you don't know how many units of Cakes will be made without doing step 3 of the answer and knowing how many grams remain for the production of cakes.