# Time to Line Up…

When you look at a digital clock, do you get excited when a cool number show ups? Like a time when all the digits are the same, or when the first two add up to the third? Only a few times each day does the clock do fun tricks like that. On a long car trip, Bedtime Math fans Miriam, Silas, and Titus R. decided to count up how many cool times clocks can show us. They figured out how many times the clock shows all one digit, like 1:11, 2:22…and remembered that those times all show up in the morning, then again in the afternoon. Can you figure out how many times have all the same digit? Let’s find out how many other cool times are worth waiting for — and how often to check the clock to catch them.

Wee ones: A clock shows the numbers 1 to 12 on it. Can you name all the numbers between 1 and 12?

Little kids: If the time is 5:55, what was the last time before that when all the digits were the same?  Bonus: Times like 2:35 are cool too, because the numbers can be an equation: here it’s 2+3=5. What equation is happening in the times 7:34 and 2:48?

Big kids: How many different times in one day does the clock show all the same digit, like 3:33?  Bonus: What’s the longest you have to wait between two of those times?

The sky’s the limit: What’s the longest you have to wait between times where the first two digits add up to the third — and there’s no 4th digit?