For the Following, Try to Come Up with an Additional

Short Answer

For the following, try to come up with an additional premise that will turn the passage into a deductively valid or an inductively strong argument. Usually this requires adding a general moral principle and, sometimes, an extra nonmoral claim as well. The idea is to guarantee that the "ought" claim follows from the "is" claim.
When Sarah bought the lawn mower from Jean, she promised to pay another fifty dollars on the first of the month. Since it's now the first, Sarah should pay Jean the money.