# Thread: Airplane Application

1. ## Airplane Application

A plane crosses the Atlantic Ocean (3000 miles) with an airspeed of 500 miles per hour. The cost C (in dollars) for each passenger is given by the following function:

C(x) = 100 + (x/10) + (36,000/x), where x is the ground speed (airspeed, plus, minus wind).

(a) What is the cost per passenger with a head wind of 50 miles per hour?

(b) What is the cost per passenger with a tail wind of 100 miles per hour?

2. Originally Posted by magentarita
A plane crosses the Atlantic Ocean (3000 miles) with an airspeed of 500 miles per hour. The cost C (in dollars) for each passenger is given by the following function:

C(x) = 100 + (x/10) + (36,000/x), where x is the ground speed (airspeed, plus, minus wind).

(a) What is the cost per passenger with a head wind of 50 miles per hour?
"head wind" means the wind is blowing against the head, that is, the plane is flying against the wind and is being slowed down. in this case, the ground speed is (airspeed - wind). so, x = 500 - wind. but wind is 50. thus, the ground speed is 450. thus, the cost is C(450), which i leave it to you to evaluate

(b) What is the cost per passenger with a tail wind of 100 miles per hour?
with a similar reasoning as above, here, x = airspeed + wind. i leave the rest to you

3. ## Great Work....

I understand what you are saying. I will do the rest.