Does the term "within 7 days" mean include the 7th day? [duplicate]

Solution 1:

I think within seven days includes the seventh day. I take it to mean "by the end of the seventh day."

For example, the American Red Cross blood donation website has this line:

• Donated platelets must be used within five days of collection.

I take that to mean the platelets can be used on Days 1, 2, 3, 4, and 5. But on Day 6, they have to be discarded.

(The fact that you were prompted to ask your question, however, is why I always state specifically that I want something returned to me by the end of the business day on a certain date.)

Solution 2:

Whenever I have a question like this I try to break it down into a smaller case and then extrapolate. If I ask to have something down "within a day" I mean 24 hours from now - today is day 0 and tomorrow is day 1, the day that it is due. So "within 7 days" means it is due on day 7, counting today as day 0.