1 Acre = 43560 square feet
1 Ton = 2000 pounds
320 Acres = 320 * 43560 square feet = 13939200 = <span>1393.92 * 10,000
</span>1393.92 *40 pounds needed = 55756.8
55756.8 / 2000= <span>27.8784 </span>
Answer:
9
Step-by-step explanation:
Cross Multiply: 
Simplify: 4x=36
x=9
Check the picture below.
make sure your calculator is in Degree mode.