Respuesta :

Answer:

1 17/39 boxes.

Step-by-step explanation:

3 1/4 rooves requires 2 2/6 boxes

So  2 rooves require 2 * 2 2/6  / 3 1/4 boxes.

= 2 * 14/6 /  13/4

= 28/6 * 4/13

= 56/39

= 1 17/39 boxes.