Respuesta :

1 : 2.5 is the constant proportionality.

1 (× 2) : 2.5 (× 2) = 2 : 5

1 (× 4) : 2.5 (× 4) = 4 : 10

1 (× 6) : 2.5 (× 6) = 6 : 15

1 (× 8) : 2.5 (× 8) = 8 : 20

Answer:

2.5 :)

Step-by-step explanation:

Explanation? My brain