`1/16` , a and b are in G.P , `1/a,1/b` and 6 are in A.P then find 72(a+b)

If a,b, and c are in A.P and b-a,c-b and a are in G.P then a:b:c is

Let (1)/(16) a and b in G.P (1)/(a),(1)/(b) 6 be in A.P., where a, b gt 0 . Then 72(a+b) is equal to ______

a,b,x are in A.P.,a,b,y are in G.P. and a,b,z are in H.P. then:

If a, b, c are in A.P. and b-a, c-b, a are in G.P. then a:b:c=?

If 1/(b-a)+1/(b-c)=1/a+1/c , then A. a ,b ,a n dc are in H.P. B. a ,b ,a n dc are in A.P. C. b=a+c D. 3a=b+c