Answer:
10/14 or about a 71% chance
Explanation:
First you add up all of the players and you get 14. If, at random the coach picks a player, to find the chance that it is not a senior just add up all of the people that arent seniors. You then get a 10 out of 14 (about 71%) chance that the coach will pick somone that is not a senior. I hope this helps :)