Question

ram's father has four sons name of first son is 25 second name is 50 third name is 75. what is the name of fourth son

Answer 1

it's obvious as it's already written that Ram's father has 4 sons and 3 of them are 25, 50 and 75....so, fourth is Ram.

Answer 2

fourth son would be Ram himself in one sense
and in another sense of series so formed by their names, he would be 100