4th Grade - Math

LESSON PROBLEM: Computation: How much do U.S. farmers grow of the world supply of rice?


American farmers are important suppliers of rice to the world. Rice is the most important grain to more than two-thirds of the world's population, followed by wheat and corn.

Rice farming has changed a lot since the first rice seed was brought to America from Madagascarin 1665 . Farmers today no longer use mules and oxen to pull farming equipment as they did on the first rice farms in South Carolina. Also, it doesn't take hundreds of man-hours per acre to plant, harvest, and prepare rice by hand. Instead, modern farmers use lasers, computers, airplanes and huge machines to help with the work.

These new methods of growing rice have improved production. In 1915, American farmers had to plant about 740,000 acres to produce 12 million hundred-pound sacks of rice. Today, U.S. farmers produce about 210 million hundred-pound sacks of rice yearly on 350,000,000 acres of land.

The six rice-producing states are Arkansas, California, Louisiana, Mississippi, Missouri, and Texas. Arkansas heads the list, growing 86,000,000 hundred-pound sacks of rice on 1,410,000 acres. California turns out 43,600,000 hundred-pound sacks of rice on 535,000 acres. That's more than a ton or two!

While America's farmers are busy raising rice, the world stands in line to buy it. The United States exports 3 million metric tons of rice a year. Only Thailand and Vietnam export more rice, at 5.5 million and 4 million metric tons, respectively.

So, who does buy our rice? Europe, Japan, and Mexico each buy more than 300,000 metric tons a year. One hundred countries throughout the world depend on us to produce rice for them to buy, including our neighbor Canada. Rice grows on all continents except Antarctica. Even so, many countries do not have land that will grow rice or some countries just can't cultivate enough rice for their people.

You can be proud that American rice farmers are experts at growing rice. There are bags of rice all over the world that say "Made in the U.S.A."


Use the information in the study guide to calculate the answers to the following questions.


1.How much rice was produced per acre in the U.S. in 1915?
2.What is the yield per acre today?
3.What is the improvement of yield per acre since 1915?
4.Which state has the highest yield of rice?
5.How much American grown rice is consumed by Americans?


Write two math questions of your own about U.S. rice production. Be sure to show how to get the answers.


  • rice
  • metric ton
  • acre
  • yield
  • laser
  • export

Click here to play Rice Rampage!
How is Rice Grown:
Farming rice is hard work. Click here to learn more about the Stages of Farming Rice.
Home | Math | Social Studies | Science | Health | Games | Students

© 2004 USRPA, A non-profit association based in Houston, Texas
All Rights Reserved

USRPA does not discriminate in its programs on the basis of race, color, national origin, sex, religion, age, disability, political beliefs, or marital/family status. Persons with disabilities who require alternative means for communication of information (such as Braille, large print, sign language interpreter) should contact USRPA at 713-974-7423.