diff --git a/practica/math/statistic/README.md b/practica/math/statistic/README.md
index 99318a8..5c2af70 100644
--- a/practica/math/statistic/README.md
+++ b/practica/math/statistic/README.md
@@ -4,12 +4,17 @@ Here you can find statistic tasks, which can be usefull in econometric calculati
 
 ## Variance
 
-- [Arithmetic mean](Arithmetic_mean.py) - the arithmetic mean of a given set of values formula
+
+
+## Statistic tasks
+- [Arithmetic mean](Statistic_tasks/tArithmetic_mean.py) - the arithmetic mean of a given set of values formula
 - [Greatest common divisor](Greatest_common_divisor.py) - calculate the GSD
 - [Least common multiple](Least_common_multiple.py) - calculate the LCM
 - [Median](median.py) - the median formula
 - [Multiplication tables](multiplication_tables.py) - multiplication tables in the form of a table of 2 horizontal and 2 vertical values
 - [Number square root](Number_square_root.py) -  the square root of the number formula
 - [Range](range.py) - the formula of mathematical range
-
+- [Mean of numbers on a segment](mean_of_nm_on_segment.py) - 
+- [Standard deviation](Standard_deviation.py) - calculate the standard deviation of list
+- [Sum](sum.py)  
 
diff --git a/practica/math/statistic/Statistic tasks/README.md b/practica/math/statistic/Statistic tasks/README.md
deleted file mode 100644
index 4286606..0000000
--- a/practica/math/statistic/Statistic tasks/README.md	
+++ /dev/null
@@ -1,6 +0,0 @@
-## Statistic tasks
-- [Mean of numbers on a segment](mean_of_nm_on_segment.py) - 
-- [Standard deviation](Standard_deviation.py) - calculate the standard deviation of list
-- [Sum](sum.py) - 
-
-
diff --git a/practica/math/statistic/Arithmetic_mean.py b/practica/math/statistic/Statistic_tasks/Arithmetic_mean.py
similarity index 100%
rename from practica/math/statistic/Arithmetic_mean.py
rename to practica/math/statistic/Statistic_tasks/Arithmetic_mean.py
diff --git a/practica/math/statistic/Greatest_common_divisor.py b/practica/math/statistic/Statistic_tasks/Greatest_common_divisor.py
similarity index 100%
rename from practica/math/statistic/Greatest_common_divisor.py
rename to practica/math/statistic/Statistic_tasks/Greatest_common_divisor.py
diff --git a/practica/math/statistic/Least_common_multiple.py b/practica/math/statistic/Statistic_tasks/Least_common_multiple.py
similarity index 100%
rename from practica/math/statistic/Least_common_multiple.py
rename to practica/math/statistic/Statistic_tasks/Least_common_multiple.py
diff --git a/practica/math/statistic/Number_square_root.py b/practica/math/statistic/Statistic_tasks/Number_square_root.py
similarity index 100%
rename from practica/math/statistic/Number_square_root.py
rename to practica/math/statistic/Statistic_tasks/Number_square_root.py
diff --git a/practica/math/statistic/Statistic tasks/Standard_deviation.py b/practica/math/statistic/Statistic_tasks/Standard_deviation.py
similarity index 100%
rename from practica/math/statistic/Statistic tasks/Standard_deviation.py
rename to practica/math/statistic/Statistic_tasks/Standard_deviation.py
diff --git a/practica/math/statistic/Statistic tasks/mean_of_nm_on_segment.py b/practica/math/statistic/Statistic_tasks/mean_of_nm_on_segment.py
similarity index 100%
rename from practica/math/statistic/Statistic tasks/mean_of_nm_on_segment.py
rename to practica/math/statistic/Statistic_tasks/mean_of_nm_on_segment.py
diff --git a/practica/math/statistic/median.py b/practica/math/statistic/Statistic_tasks/median.py
similarity index 100%
rename from practica/math/statistic/median.py
rename to practica/math/statistic/Statistic_tasks/median.py
diff --git a/practica/math/statistic/multiplication_tables.py b/practica/math/statistic/Statistic_tasks/multiplication_tables.py
similarity index 100%
rename from practica/math/statistic/multiplication_tables.py
rename to practica/math/statistic/Statistic_tasks/multiplication_tables.py
diff --git a/practica/math/statistic/range.py b/practica/math/statistic/Statistic_tasks/range.py
similarity index 100%
rename from practica/math/statistic/range.py
rename to practica/math/statistic/Statistic_tasks/range.py
diff --git a/practica/math/statistic/Statistic tasks/sum.py b/practica/math/statistic/Statistic_tasks/sum.py
similarity index 100%
rename from practica/math/statistic/Statistic tasks/sum.py
rename to practica/math/statistic/Statistic_tasks/sum.py