stats help!

[jaded_chick]

please help me with stats so i may get the 50% needed to pass this horrid horrid course.

A sample of n=15 has a mean of 4.00. A second sample of n=6 has a mean of 10.00. If the two samples are combined into one large sample, the mean of the total sample
= 5.71 .

how did they get 5.71 as the answer.

thanks

 

[Kaksback]

n=21

 

[Kaksback]

n=15 with a mean of 4.00 which means the total sum of the N equaled to 60

n=6 with a mean of 10.00 means the total sum of the N's equaled to 60 as well.

60 plus 60 = 120

6+15 = 21

 

[Y_lifter]

Thanks for dredging up this Nightmare...

 

[Kaksback]

lol i have no clue about stats...sorry jaded chick..just took a whack at it..

i havent taken stats before...its weird when i think about it and talk to my friends who have taken it..its def. different from the math I took (i took up to Calculus II in college)

go figure