A Backwards Day

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 4/24/24, which means the 24th day of the 4th month. In fact, we’re in a whole stretch of palindrome days that will last through 4/29/24. Don’t forget, 4/2/24 and 4/20/24, 4/21/24, 4/22/24 and 4/23/24  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 424? Bonus: How old will you be the next time your age is the same backwards and forwards?

Big kids: The digits of 4/24/24 add up to 16 (4 + 2 + 4 + 2 + 4). Will there be any dates in August this year that add up to 16? Bonus: What is the last date in 2024 with digits that add up to 16?

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 424 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: Yes, because August is only the 8th month, that leaves the dates 8/2/24, 8/11/24, and 8/20/24 to add up to 16.  Bonus: 12/25/24: 1 + 2 + 2 + 5 + 2 + 4.

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!

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