Question

The means of two groups of n and 12
observations are 33 and 40
respectively and the combined group
mean is 36. The value of n is​

Answer 1

Answer:

Let in common no. in each group is X

Then Member of each group is 2X,3X and 5X

Total of three group =(2X+3X+5X)12=120X(given mean of three group is 12)

And total of Two group =(2X+3X)3=15X (given mean of two group is 3)

Then total of third group =120X−15X=115X

Mean of third group =

5X

115X

=21