You know that the ratio of J&S to F&So is 2:3. You need two numbers that have that same ratio to total 60 players.  When you multiply both numbers by 12, you have a ratio of 2:3 but the number of players is 24 to 36.  Thus, the total players is 60.  When looking at the ratio of Juniors to Seniors, the ratio remains 1:2, but must total 24 players.  Dividing the total players by 3, you can find where 1 part of the players equals 2 parts of the others.  Keeping that same ratio in mind, you are able to calculate that the ratio of Juniors to Seniors is 8:16 but when reduced, still remains a 1:2 ratio.