G, I must be missing something. If you get paid 50% of your investment
immediately and the other 50% halfway through, then surely you have your
total investment back after term/2 days. That of course is 'way too simple
to need to ask about.

The next most likely scenario I can think of is this: You're investing 50%
of <amt up front, and someone starts making regular payments back to you,
once a period for <n periods. Halfway through the agreed number of periods
you invest the other 50% of your agreed investment. You're asking how to
calculate <n. But that doesn't work either, for any calculation like that
includes interest, and you didn't mention it.

So can you rephrase the question?

--- "G" wrote:
I am trying to figure out how to count the number of days it takes to get
paid back the investment that was paid 50% upfront and 50% midway through
the term of the deal.