Which is the better investment: Noncumulative, nonparticipating, preferred stock with a preferred stock with a $4-per year dividend rate, each share cost $20 or Noncumulative, nonparticipating, preferred stock with a preferred stock with a $4-per year dividend rate, each share cost $25

This is very easy if you'd stop making this some difficult percentage thing and just think about what it says. They both have the same payout with no differences at all. Would you rather pay $20 or $25 for it?