diff --git a/00.brainstorming-pedagogical-teams/45.synthesis-structuring/10.math-tools/40.n4/12.en/textbook.en.md b/00.brainstorming-pedagogical-teams/45.synthesis-structuring/10.math-tools/40.n4/12.en/textbook.en.md
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----
-title: Brainstorming on the mathematical tools required at each level
-published: true
-routable: true
-visible: false
-lessons:
-    - slug: define-234-mathematical-tools
-      order: 3
----
-
-#### Define the mathematical tools required at level 4
-
---------------------------------
-
-with a **first classification to order the brainstorming a little** (counting, geometry, etc.).   
-It *does not presage chapter titles *.
-
-Feel free to create a new classification if necessary.
-
-
-! *xxx*
-!
-
-(XXX-YY)
-...
-
---------------
-
-(XXX-YY)
-...
-
--------------- 
\ No newline at end of file