Practice your 1L exams. Don't just reread your outline.

A printing company in Missouri offered to buy a used binding machine from a neighboring shop for $6,500. The buyer emailed a written offer on Friday, March 8. It stated: "I will keep this offer open until March 15. Please mail your written acceptance to my office." The buyer did not say that acceptance had to be received before the deadline, and neither party paid for an option contract. The seller inspected the machine over the weekend and decided to accept. On Monday morning, March 11, the seller signed an unconditional acceptance, placed it in a properly addressed envelope with sufficient postage, and deposited it with the U.S. Postal Service. The seller did not send an email or telephone the buyer. The post office stamped the envelope with a March 11 postmark. Its receipt shows that the mailing address was complete and correct. Both businesses had used ordinary mail for the exchange of signed documents in earlier transactions, and the seller had no reason to think that the buyer expected delivery by courier. Early Tuesday, before the acceptance letter arrived, the buyer found a cheaper machine from someone else and called the seller to revoke the offer. The seller responded that the acceptance was already in the mail. The letter was delivered Thursday. The parties disagree about whether they entered a contract. The buyer argues that the Tuesday telephone call was effective immediately and that delivery of the acceptance did not occur until Thursday. The seller points to the offer’s express invitation to respond by mail and insists that the Monday mailing—not Thursday delivery—is the relevant event.