More Children and Plants


From notes of Plants
 

So if pupils consider the areas D, E, F and G as "worth" more than 1, (D, E, F being 2 and G 3), then tables like this can sometimes result. There's a lot to explore in these tables, and it's interesting at the start to find out how the pupils do the explorations to get the table. Some may be using a spreadsheet, mental calculations, looking at the picture of three overlapping circles whilst others may use something practical to check that all is well with their ideas. Some interesting discussions may arise from some pupils who work very arithmetically and come up with a system but unfortunately ignore the maximum number allowed in each circle. B/ Explore other groups of numbers instead of just 5, 6 and 7 - what about numbers going up in 2s, 4s, 6s and 8s or just random numbers 3s, 6s and 7s? C/ If pupils have happily constucted tables like those above in which every possibility is discovered you might explore the number of possibilities according to the difference between the total for the three circles, (5+6+7) and the number of items used. For example there were 7 solutions for a difference of two. 
 
 
Further exporation will reveal the number of solutions when 3, 4, 5 etc extra ones are needed (e.g. when 13 items are used with 5, 6 and 7 circles then there an extra (18 - 13) 5 items are needed.
For the highest-attaining Obvious extension work can be looked at by considering four areas - though not all are circles in this diagram - and asking similar questions.