Let x represent the number of pounds of seed needed per acre.
it takes 89 pounds of seed to completely plant a 11-acre field. We would set up the following equations
89 = 11
x = 1
By crossmultiplying, we have
89 * 1 = x * 11
89 = 11x
Dividing both sides of the equation by 11,
x = 89/11
x = 8.09
8.09 pounds of seed are needed per acre