Ask students to watch Futures Channel Movie #2005 and to try to notice as many variables as they can that are related to farming. When the movie is over, make a list of variables that students noticed (amount of rice produced, amount of rain, number of acres planted, size of silos, how much rice is sold, how long it takes to harvest the rice, etc.).
Explain that a farmer like Bryce Lundberg often has to compare two different values when he is planning crop production, and give a few examples related to the variables that have been listed (e.g., comparing sales of different kinds of rice, or comparing the number of acres planted with the pounds of seed need to plant them, or comparing the cost of operating the harvester with the total number of days required to harvest).
Explain further that it is often helpful to compare these numbers by dividing, and discuss a few examples of this (e.g., compare 100 tons of basmati rice sold to 300 tons of wild rice by dividing to find that three times as much white rice was sold, compare 12,000 pounds of seeds planted with 60 acres to find that you used 200 pounds for each acre).
Ask students if they know the word that means “a comparison of two quantities by dividing”, and elicit or provide the answer of ratio. Explain that students will be learning how to work with ratios in this chapter. |
