That's incorrect. A typical piano has one string on the bass notes, then two strings per note as you get higher up the keyboard, then three per note higher up a

That's incorrect. A typical piano has one string on the bass notes, then two strings per note as you get higher up the keyboard, then three per note higher up again. The exact point where the switch is made varies a little. If you meant "typically" as in the majority, the majority of the keys have three strings.