x (Six)
e - One o - Two e - Three r - Four e - Five x - Six
Think out of box?
What will be next in the series? O, T, T, F, F, S, S ,_ ,_ ,_ ; ?
What's next in the following series - A) 3, 3, 5, 4, 4, 3, 5 ..., B) O, T, T, F, F, S, S, ... (HINT - they are related)