In a harmonic sequence, the first term is 1/2, and the third term is 1/8. The harmonic mean between the two terms is

Answer 1

1/5 is the 2nd term

1/2, 1/5, 1/8, 1/11, 1/14, 1/17, 1/20, 1/23, 1/26, 1/39, 1/32, ... are the 1st 11 terms of the harmonic sequence

the denominator increases by 3 each term

nth term is 1/(2+3(n-1)= 1/(3n-1)

2nd term = 1/[(3)(2)-1]=1/(6-1)= 1/5

1/5 is the harmonic mean of 1/2 and 1/8

general formula = 2xy/(x+y)

if x=1/2 and y=1/8

then 2(1/2)(1/8)/(1/2+1/8)= (1/8)/(5/8)= 1/5