Respuesta :

Answer: 15

Step-by-step explanation: 50 times 2 is 100, 30 divided by 100 is 0.3, 50 times 0.3 is 15, and 15 times 2 is 30

Sorry if this is wrong :p

15. The ratio of skateboarders is 1:2. If you apply this to the long boarders it would be 30/2 which equals 15.