Please solve this Word Problems.

Question

1. Shipping charges are often based on a formula that offers a lower charge per pound as the size of the shipment is increased. Suppose shipping charges are as follows: $2.20 per pound if the weight does not exceed 50 lb; $2.10 per pound if the weight is more than 50 lb but does not exceed 200 lb; $2.05 per pound if the weight is more than 200 lb.

a. Find a mathematical model expressing the total cost of a shipment as a function of its weight.

 

2. A person’s approximate brain weight is directly proportional to his or her body weight, and a person weighing 150 lb has an approximate brain weight of 4lb.

 

a. Find a mathematical model expressing the approximate brain weight of a person as a function of the person’s body weight.
b. Find the approximate brain weight of a person whose body weight is 176 lb.

Answer 1

I'm going to have to think about problem 1 for a while

 

2a.  W_(brain)/W_(body) = (4 pounds)/(150 pounds)

 

Therefore W_(brain) = [(4 pounds)*W_(body)]/(150 pounds)

 

2b. W_(brain) = [(4 pounds)*(176 pounds)]/(150 pounds) = 4.7 pounds