Question

Sara received a puppy when she was 7 years old. The puppy weighted 5 pounds. When the puppy grew up, it weighed 12 pounds. What was the percentage of increase in the puppy’s weight? Show your work

Answer 1

The puppy gained 7 pounds. So, we must wonder: which percentage of 5 is 7? We can write the proportion

$7\div 5=x\div 100$

and solving for x we have

$x=\dfrac{700}{5}=140$