STEEM:

Bitcoin:

Sort the post order by "age" and check the first 25 entries(first 50 entries for ARK contest).
The one has the closest prediction to the closed price will be the winner.
If you think you are the winner, just leave a comment below such as “STEEM, BTC, EOS, ARK(+ your ARK address wallet.), ETH or LTC + your entry numbers”.
I will use the reward (STEEMs) to power up the winner accounts before the end of the day.
Unclaimed rewards will be expired within 24 hours.
If you have any question, please do not hesitate to leave your comment below!