A plane that flies 220mph is flying 550miles. How long will the trip take?
This plane will take 2.5 hours to fly this distance as long as it flies at that speed for its whole journey.
Assuming that the airplane will fly at the same speed the whole time, the way to find this out is to divide the number of miles the plane has to fly by the speed it will fly. This will give you a number in hours.
So, we take the number of miles the plane needs to fly, which is 550. We divide it by 220, which is the speed of the airplane. This gives us 2.5.
You divide the number of miles the plane is flying--550--by the number of miles the plane can fly in an hour--220. The answer is 2.5 hours.
Think about what you already know and what you want to know.
You already know that "mph" means miles per hour. You already know that the plane is flying 220 miles per hour. You already know that the plane is traveling 550 miles. You WANT to know how many hours (how long) the trip will take. This means that you can set up your problem as a "porpoprtion" - two equal fractions. Since "per" means divide, or fraction you can write:
200miles divided by 1 hour = 550 miles divided by ? hours.
To solve this multiply the opposites (when its in fraction form it will be "multiply the diagonals and divide by what's left"). So multiply 550 miles by 1 hour, = 550. Now divide by what's left --220. 550 divided by 220 = how long (in hours) the trip will take.