Want to keep learning?

This content is taken from the UEA (University of East Anglia)'s online course, Preparing for University. Join the course to learn more.

Skip to 0 minutes and 4 seconds 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.

Skip to 1 minute and 9 seconds 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.

Solution to the cake question

The video here gives the solution to the questions in the previous step comparing the masses of two cakes

Have a go at another problem. For this question you need to know that 1lb = 454g and 14lbs = 1 stone.

There are three people from different countries which use different measurements to determine their mass. Work out which of the three is the heaviest: An Englishman with a mass of 13st 5lbs, an American with a mass of 191lbs or a Frenchman with a mass of 88.3kg.

The answer is in the video in the next step.

Share this video:

This video is from the free online course:

Preparing for University

UEA (University of East Anglia)

Get a taste of this course

Find out what this course is like by previewing some of the course steps before you join: