The number of packs is 5.
Let the number of juicy packs of gum bought by Marisol be represented by n.
Adeline bought 8 packs of Fun gum with each pack containing 7 pieces of gum.
Total number of gums has Adeline = 8 x 7
Total pieces of gum has Marisol = n x 9
Given that Adeline has 11 more pieces of gum than Marisol, thus;
56 = 9n + 11
56 - 11 = 9n
45 = 9n
n = 5
The number packs of juicy gum bought by Adeline is 5 and total pieces of his gum is 45.