A palindrome is a word that is spelled the same backwards and forwards, like toot and racecar. Can you think of any others? It turns out numbers can do the same thing — like today’s date! Today is written as 3/21/23, which means the 21st day of the 3rd month (March). In fact, we’re in a whole stretch of palindrome days that will last through 3/21/23. Don’t forget, 3/2/23 and 3/20/23 were palindromes, too! Let’s see how often these cool dates happen.
Wee ones: How do you say “123” in backwards order?
Little kids: If you say “321” in backwards order, is it the same or different? How about 454? Bonus: How old will you be the next time your age is the same backwards and forwards?
Big kids: The digits of 3/21/23 add up to 11 (3 + 2 + 1 + 2 + 3). What’s the next date (using 2 digits for the year) with digits that add up to 11? Bonus: Are there any more future dates in 2023 with digits that add up to 11?
The sky’s the limit: If you’re allowed to write both the month and year as 2 digits, when’s the first year when we won’t have any palindromic dates? (For example, in 2030 you can write March as 03).
Answers:
Wee ones: 321.
Little kids: 321 then reads 123, so it’s not a palindrome. But 454 does work! Bonus: Different for everyone…any single digit works, like 7, 8 or 9! Or your next age might be 11, or 22…or 101!
Big kids: 3/30/23. Bonus: 4/2/23, 4/11/23, 4/20/23, 5/1/23, 5/10/23.
The sky’s the limit: In 2100. We’ll have palindromic dates in 2022 (2/20/22, 2/21/22…), and in 2023 we can have them in March (3/20/23 through 3/29/23, plus 3/2/23). Then in 2024 we’ll have 4/2/24, 4/20/24, 4/21/24 and so on. That’s true throughout the ’20s, with dates like 5/20/25, all the way through 9/29/29. In 2030 we start over with 03/1/30, then 1/3/31. This pattern will continue through the ’40s, ’50s, all the way to 9/9/99 in 2099. 2100 is the first year we won’t have a palindromic date, because we can’t have 0/0/00!
