Respuesta :

carlosego
For this case we must find:
 x = the number of marbles in a package.
 For this, according to the statement we have the following equation:
 7x + 9 = 30
 Clearing x we have:
 7x = 30-9
 x = 21/7
 x = 3 marbles
 Answer:
 Each pack of marbles contains 3 marbles