The New Year (Math) Resolutions
When the end of each year approaches, teachers often make this joke at schools. They told the students that they would collect the assignment back next year. Since these are the last days of the year, the students have just two or three weeks to do their tasks. It is the holiday season, and even you could not count it as spare time. Everyone says that 2020 is the worst year ever; I will not argue that everyone is locked down in their homes because of the pandemic. So, you might have more time in this holiday season, any way you do not have one year. If you are a somewhat selfish (!) math teacher like me, you can assign homework a month before, especially in project assignments, make this joke, and get the first teacher’s title making this joke in the school.
While approaching the new year, some questions might ask only by math teachers. These kinds of problems seem fun, but they challenge the problem-solving ability of students. One of them is here:
How can someone born in 2021 be older than someone born in 2020?
An answer could be 2021 before Christ (2021 BC) and 2020 after Christ (2020 AC). However, since we are talking about the new year here, it may be useful to state that both dates are after Christ. Or you can also take that as an answer and make the math a little more fun in your students’ eyes. Of course, you need to mention as a second answer, the real one.
Aside from the joke, could there be such a situation?
Could someone be older than someone born in 2021 and also born in 2020?
This situation happens in real life. When we look at the births’ projections in the last decades, the number of such people can vary between approximately 150 thousand and 200 thousand. Since 2020 is a slightly different (!) year, the number of babies will increase during the pandemic process, everyone is at home, and nothing too much to do, so I wanted to keep my forecast range-wide. In the meantime, I also gave you a clue about how it happened and how you could answer the question. The number of babies born in…