Solution to the cake question

The problem here is to distinguish which cake weighs heaviest. Cake one, which is 3/17 of a 2.7 kilogramme cake, or cake two, 2/13 of a 3.1 kilogramme cake. The difficulty here arises from the fact they you have different proportions of different cakes with different masses. So in fact, if you multiply 3/17 by 2.7 kilogrammes, you will get the mass of cake one that you have. So 3/17 multiplied by 2.7 kilogrammes equals 0.4764 kilogrammes. Similarly for cake two, if you multiply 2/13 by 3.1 kilogrammes, you will get the mass of cake two that you have. So 2/13 multiplied by 3.1 kilogrammes equals 0.4769 kilogrammes.

As you can see these two masses are very similar, and it would have been extremely difficult to determine this without this piece of mathematics. But by comparing the two numbers, you can see that cake two is the heaviest.