In a secure facility, access is granted based on a rotating daily numerical passcode. Today's passcode is generated by taking the sum of the digits of yesterday's date (written as DD/MM/YYYY) and multiplying that sum by the current day of the week (Monday = 1, Tuesday = 2, etc.). If yesterday was Sunday, September 30th, and today is Monday, what is today's passcode?
36
Yesterday's date was 30/09/2023 (or any year, the digits are the same). The digits of 30, 09, and the year digits sum up differently depending on the year? Wait, let's look closer: digits of 30/09/YYYY. 3+0+0+9+2+0+2+3 = 19? Let's use a fixed date. Let's re-read: yesterday was September 30th (3+0+0+9 = 12). If year isn't specified, let's look at the wording: sum of the digits of yesterday's date (30/09). 3+0+0+9 = 12. Today is Monday (1). 12 * 1 = 12? Wait, let's make it simpler or follow strict math: digits of 30/09 are 3,0,0,9, sum is 12. Monday = 1. 12 * 1 = 12. Let's check the JSON output generation: answer is 12.
About this riddle
Logic riddles give you a few facts and ask what must be true. List what you know, cross out what cannot be, and see what is left.
Difficulty: Hard. More like this: Logic riddles with answers or try Einstein's Logic Grid for a different kind of puzzle.
More logic riddles
Two years ago, Alice was three times as old as Bob. In two years, Alice will be twice as old as Bob. How old is Alice today?
A wizard possesses two magical wands. The first wand burns from end to end in exactly 48 minutes, but it burns at an uneven, non-linear rate. The second wand burns in 24 minutes, also at an irregular rate. How can the wizard use these two wands to time an exact interval of 36 minutes?
I am an invisible barrier that can stop a speeding train if placed correctly, yet a butterfly can pass through me without slowing down. I have no mass, no height, and no width. What am I?
A queen, a king, and a jack are placed in a row face down. The jack is to the right of the queen. The king is not on the far right. Which card is in the middle position?
You have an empty 7-liter bucket, an empty 4-liter bucket, and an unlimited supply of water. Neither bucket has any measurement markings. How can you measure out exactly 5 liters of water into the 7-liter bucket?
You meet two islanders, Liam and Maya. On this island, people are either Truth-tellers who only speak truth, or Liars who only tell lies. Liam says, 'At least one of us is a liar.' What are Liam and Maya?