24) All percents are numbers with the decimal moved 2 to the right. So if you have 275%, move the decimal to the left twice to get a factor of 2.75. that means that the puppy is 2.75 times heavier at 4 months than it was at 2 months. Since you need the answer as a mixed fraction, your answer is;

28) If 6 of 75 trees are 30+ feet tall and you need to know how many are under, subtract 6 from 75 to get (75 - 6) = 69 trees under 30ft tall.
You're looking for the percent of trees under 30ft tall, so divide the number of trees <30ft by the total number of trees to get;

Move the decimal 2 to the right to get
92%.
Your answer is that
92% of trees is under 30ft.
2(-3n-5)-5(4n-8)
(-6n-10)+(-20n+40)
-26n-30
It depends on how many options you have
You multiply the total number of books you have time 5 because you can choose 5