Answer:
66.7%
Step-by-step explanation:
Given that,
Weight in first five weeks = 4.5 pounds
Weight at eight weeks = 7.5 pounds
We need to find the increase in precentage. The percentage increase in any value is given by :
[tex]\%=\dfrac{\text{final-initial}}{\text{initial}}\times 100\\\\=\dfrac{7.5-4.5}{4.5}\times 100\\\\=66.7\%[/tex]
So, the increase in precentage is 66.7%.