1. There are two experimental fields of wheat with equal area. The first one uses the original variety, and the second one uses the new variety. 9 tons and 15 tons of wheat are harvested respectively. It is known that the average yield of the first experimental field is 3 tons less than that of the second one. The average yield of these two experimental fields per hectare is calculated respectively

1. There are two experimental fields of wheat with equal area. The first one uses the original variety, and the second one uses the new variety. 9 tons and 15 tons of wheat are harvested respectively. It is known that the average yield of the first experimental field is 3 tons less than that of the second one. The average yield of these two experimental fields per hectare is calculated respectively

The key of solving practical problems with equations is to find the equivalent relation, which is equal area
9/x=15/(x+3)
Then it's solving the equation~