Question

Let the positive numebrs a,b,c,d be in A.P. Then `abc,abd,acd,bcd` re (A) not in A.P., G.P., H.P. (B) in A.P. (C) in G.P. (D) in H.P.
A. not in A.P./G.P./H.P.
B. in A.P.
C. in G.P.
D. in H.P.

Answer 1

Correct Answer - D
It is given that
a,b,c,d, are in A.P.
`rArr" "d,c,b,a` are in A.P.
`rArr" "(1)/(d),(1)/(c),(1)/(b),(1)/(a)` are in H.P.
`rArr" "(abcd)/(d),(abcd)/(c),(abcd)/(b),(abcd)/(a)` are in H.P.
`rArr" "` abc,abd,acd,bcd are in H.P.