Answer: There are 5 boxes all labeled 9. Each box is 20%.
Explanation:
If you take this equation: 20%*a(adult weight)=n(new puppy weight) and plug in the values, the equation would be 20%*45=9. You can check that the equation is correct by multiplying 0.2*45 which will equal 9. The five boxes are all 20% and there are 5 20%'s in 100%.
Hope this helps! :)