Question

The mean of groupA is 4times the mean of groupB the number observation of groupA is 1/7th the number of observation groupB. If x-c is the combine mean then find the ratio of x-c:x-a

Answer 1

Explanation:

Let mean of group B be x

It is 4 times group B so

Mean of grop A = 4x

n1=n/7 n2=n

Applying formula of combined mean we get

Xc=5x/8 and X1=4x

so ratio will be 5 is to 4