This was confusing to me as a kid, especially as we entered the 21st. I also still remember learning about the Dutch golden age in elementary school, but can't

This was confusing to me as a kid, especially as we entered the 21st. I also still remember learning about the Dutch golden age in elementary school, but can't remember if it was the 1600s or 16th century. I'm running into a similar issue recently. Turns out that many people saying they are '7 months pregnant' actually mean they are in the 7th month, which starts after 26 weeks (6 months!)