The correct answer is:
1250 skiers and 2500 snowboarders.
Step-by-step explanation:
The ratio is 1:2. We are told that more snowboarders buy season tickets than skiers; this means the ratio is skiers/snowboarders.
Let x be the number of skiers that bought season tickets. Since 1250 more snowboarders bought season tickets, this means the number of snowboarders would be represented by x+1250.
We can use the ratio to set up a proportion:

Cross-multiply:
(x+1250)(1) = x(2)
x+1250 = 2x
Subtract x from each side:
x+1250-x = 2x-x
1250 = x
This means the number of skiers is 1250.
The number of snowboarders would then be 1250+1250 = 2500.