A grain farmer has 100 acres available for sowing oats and wheat. The seed oats cost $5 per acre and the seed wheat costs $8 per acre. The farmer expects a profit from oats of $220 per acre and from wheat $250 per acre. How many acres of each crop should he sow to maximise his profit, if he does not wish to spend more than $620 for seed and $1800 for labor?
