Find the mean of the following distribution.


x:



10



12



20



25



35



f :



3



10



15



7



5



x



f



fx



10



3



30



12



10



120



20



15



300



25



7



175



35



5



175




N = 40



∑fx = 800



Therefore, mean () =


=


= 20


Therefore, = 20


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