question_answer

Given that n A.M.'s are inserted between two sets of numbers a, 2b and 2a, b, where a, \[b\in R\]. Suppose further that \[{{m}^{th}}\]mean between these two sets of numbers is same, then the ratio a : b equals

A)  \[n-m+1:m\]    

B)  \[n-m+1:~n\]

C)  \[n:n-m+\text{1}\]        

D)  \[m:n-m+\text{1}\]

E)  None of theses