Test
x ¯ r = 1 c ∑ c x c , r {\displaystyle {\bar {x}}_{r}={\frac {1}{c}}\sum _{c}x_{c,r}} x ¯ c = 1 r ∑ r x c , r {\displaystyle {\bar {x}}_{c}={\frac {1}{r}}\sum _{r}x_{c,r}} x ¯ = 1 r c ∑ r , c x c , r = 1 r ∑ r ( 1 c ∑ c x r , c ) = 1 r ∑ r x ¯ r {\displaystyle {\bar {x}}={\frac {1}{rc}}\sum _{r,c}x_{c,r}={\frac {1}{r}}\sum _{r}({\frac {1}{c}}\sum _{c}x_{r,c})={\frac {1}{r}}\sum _{r}{\bar {x}}_{r}}
Zobacz więcej w osobnym artykule: Powstanie warszawskie.
