solution:
For a freely falling body initial velocity (u)=0
for a body which travelled in nth second distance
Sn=u+ a(n-1/2)
for freely falling body acceleration(a)=g
for 2nd second S2=g(2-1/2)
=g(3/2)
for 3rd second S3=g(3-1/2)
=g(5/2)
the ratio between is 3/2g:5/2g=3:5