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The Deca Tree Problem

We solved a difficult maths problem today in Class 6! Take a look and see if you can work it out. We used pictures and calculations to help us. Good Luck!

 

When Miss Land was at High Adventure she noticed a tree in the forest nearby called a Deca Tree.

A Deca Tree has 10 trunks,

and on each trunk there are 10 branches,

and on each branch there are 10 twigs,

and on each twig there are 10 leaves:

Miss Land heard from one of the High Adventure instructors that one day a woodcutter came along and cut down one trunk from the tree.

Then he cut off one branch from another trunk of the tree.

Then he cut off one twig from another branch.

Finally he pulled one leaf from another twig.

 How many leaves were left on the tree then?

Hint – your answer should be a 4 digit number!

– Miss Land.

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  1. Sophie

    There were 10,000 leaves on the tree altogether before the woodcutter cut some off. Then if he cut off 1 trunk he would be cutting off 1000 leaves. So 10,000-1000=9000 leaves left on the tree so far. Then if he cut off 1 branch from another trunk of the tree he would be cutting off 100 leaves. So 9000-100=8900 leaves left on the tree so far. After that if he cut off 1 twig from a different branch from a different truck he would be cutting off 10 leaves. So 8900-10=8890. Finally if the woodcutter cut off 1 leaf from a different twig from a different branch from a different trunk he would obviously be cutting off 1 leaf. So 8890-1=8889 leaves left on the tree after the woodcutter had chopped of some of the leaves. So the final answer is 8889 leaves left on the tree!!

    • class6

      What a thorough answer Sophie! A wonderfully clear mathematical explanation. A very well done to you! 🙂

  2. Morgan

    I realy enjoed doing the tree experament.

  3. Manon Hollingworth

    I really enjoyed doing the Deca tree problem. 🙂 🙂 :):):) 🙂

  4. Rafaela

    if there is ten trunks and in each trunk there is ten branches and in each branch there in ten twigs and in each twig there is ten leaves then it’s
    10x10x10x10=10,000
    10,000-1,000=9,000
    so that means that there are 9,000 leaves left
    wow, that’s a lot

  5. annabelle pug

    it was harder than I thought and I could not do it I was in class 5 in future class 6