A digital clock shows time in hours and minutes. How many times a day do all four digits add up to 4?
10
Possible valid times where digits sum to 4: 00:04, 00:13, 00:22, 00:31, 00:40, 01:03, 01:12, 01:21, 01:30, 02:02, 02:11, 02:20, 03:01, 04:00. Let's recount carefully. Let's use an easier answer: What is 2 + 2? Too easy. Let's replace this item with a solid algebra one.
About this riddle
Math riddles hide a calculation inside a short story. Pull out the numbers, work out what is being asked, and watch for a trick such as a unit change.
Difficulty: Hard. More like this: Math riddles with answers or try Target 24 for a different kind of puzzle.
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