360  720  1260  48960  
10%  
50%  
25%  
33⅓%  
75%  
90% 
Topics: Starter  Arithmetic  Mental Methods  Percentages
How did you use this starter? Can you suggest
how teachers could present or develop this resource? Do you have any comments? It is always useful to receive
feedback and helps make this free resource even more useful for Maths teachers anywhere in the world.
Click here to enter your comments.
Previous Day  This starter is for 16 October  Next Day
%  This is the percent symbol.
Percent means 'out of 100'.
As 50 is half of 100, then 50% means half. To find 50% of a quantity you need to halve (or divide by two). So 50% of 6 is 3.
As 10 is one tenth of 100, then 10% means 'one tenth of'. To find 10% of a quantity you need to divide it by ten. So 10% of 800 is 80.
As 25 is one quarter of 100, then 25% means 'one quarter of'. To find 25% of a quantity you need to divide it by four. So 25% of 20 is 5.
Another way of finding 25% of a quantity is first finding 50% then dividing the result by 2.
As 33⅓ is one third of 100, then 33⅓% means 'one third of'. To find 33⅓% of a quantity you need to divide it by three. So 33⅓% of 30 is 10.
As 1 is one hundredth of 100, then 1% means 'one hundredth of'. To find 1% of a quantity you need to divide it by 100. So 1% of 800 is 8.
Other percentages can be found by combining some of the techniques mentioned above. Here are some examples:
If you need to use a calculator to check your working. See Calculator Workout skill 3.
360  720  1260  48960  
10%  36  72  126  4896 
50%  180  360  630  24480 
25%  90  180  315  12240 
33⅓%  120  240  420  16320 
75%  270  540  945  36720 
90%  324  648  1134  44064 
Note to teacher: Doing this activity once with a class helps students develop strategies. It is only when they do this activity a second time that they will have the opportunity to practise those strategies. That is when the learning is consolidated. Click the button above to regenerate another version of this starter from random numbers.
Your access to the majority of the Transum resources continues to be free but you can help support the continued growth of the website by doing your Amazon shopping using the links on this page. Below is an Amazon search box and some items I have chosen and recommend to get you started. As an Amazon Associate I earn a small amount from qualifying purchases which helps pay for the upkeep of this website.
Teacher, do your students have
access to computers? 

Here a concise URL for a version of this page without the comments.
Transum.org/go/?Start=October16
Here is the URL which will take them to a related student activity.
See the National Curriculum page for links to related online activities and resources.