There are eight persons, A, B, C, D, E, F, G and H, all having different weights. Only two persons are lighter than F. F is heavier than A but lighter than B. D is lighter than E but heavier than G. H is lighter than A. C is heavier than E. C is not the heaviest person. The weights of the second heaviest and the second lightest persons are 78 kg and 48 kg, respectively. How many persons are lighter than the person who is just lighter than D?

Three

A, B, C, D, E, F, G and H.

1) Only two persons are lighter than F.

So, _> _> _> _> _> _> F> _> _

2) F is heavier than A

3) His lighter than A.

So, _> _> _> _> _> F> A> H

4) C is heavier than E.

5) D is lighter than E but heavier than G.

6) C is not the heaviest person.

So, _> C> E> D > G> F> A> H

7) F is lighter than B.

B> C> E> D > G> F> A> H

The weights of the second heaviest and the second lightest persons are 78 kg and 48 kg.

So, B > C(78 kg) > E > D > G > F > A(48 kg) > H 

Here, G is just lighter than D.

And, Three persons are lighter than G.

So, there are Three persons are lighter than the person who is just lighter

than D