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Let 1 be the A.M and 2 be the G.M of two numbers a and b. Then their H.M is
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- 4 ans.
sol(1):-
since,G.M^2=A.M*H.M
Therefore,H.M=G.M^2/A.M=2^2/1=4 ANS.
OR,
SOL(2):-Since,
A.M=(a+b)/2 -> a+b=2*1=2---(i)
G.M=(ab)^1/2 -> ab=2^2=4---(ii)
and H.M=2ab/(a+b)=2*4/2=4 ans. [using eq-n (i) and (ii)]
- 12 years agoHelpfull: Yes(12) No(1)
- AM=(a+b)/2-->1
GM=root(ab)-->2
HM=2ab/a+b-->3
given AM=1
a+b=2
given GM=2
GM^2=4
from 2 ab=4
by sub a+b=2 and ab=4 in eq 3
HM=2*4/2
HM=4 - 12 years agoHelpfull: Yes(2) No(1)
- A.M. OF a and b = a+b/2 =1. So a+b = 2
G.M. OF a and b = √ab =2. So ab =4.
Putting the value in the below given formula.
H.M. OF a and b =2ab/a+b= 2*4/2=4.
So the ans is 4.
- 12 years agoHelpfull: Yes(1) No(0)
- here A.M=a+b/2=1==>a+b=2
G.M=ab=2^2=4
HM=2ab/(a+b)=2*4/2=4
HM=4 - 12 years agoHelpfull: Yes(1) No(0)
- Harmonic mean is 4
a+b=2
ab=4
2ab/a+b=4 - 12 years agoHelpfull: Yes(1) No(0)
- G=(A*H)^1/2
So,harmonic mean=1/2 - 12 years agoHelpfull: Yes(1) No(0)
- A.M * H.M= (G.M)2
1/(2)^2 = 1/H.M
H.M=4 - 12 years agoHelpfull: Yes(0) No(0)
- Ans.4
(G.M.)^2=A.M.*H.M.
(2)^2=1*H.M.
H.M.=4 - 12 years agoHelpfull: Yes(0) No(0)
- AM * HM =GM^2
so, HM = 4/1 = 1 - 11 years agoHelpfull: Yes(0) No(0)
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