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🎃 + 🍬 = $1.10

The pumpkin costs exactly $1 more than the candy. How much is the candy? Lock in your gut answer.

← BlogAug 30, 20263 min read

13 Halloween riddles that trick your brain

Heron
I'm Heron. I wear a flamingo costume every Halloween, and it fools no one. The candy question above once fooled me, though, and I coach mental math for a living. Let's make sure it never gets either of us again.

The Candy Trap: why 10¢ feels so right

The poll up top has one job: to rush you. A pumpkin and a candy for $1.10, the pumpkin a dollar more, and most brains instantly slide 10¢ across the counter. Fast, confident, wrong.

Let's check it together. If the candy costs 10¢, the pumpkin costs $1.10, and the pair rings up at $1.20. Ten cents over. The real split is candy 5¢, pumpkin $1.05: exactly $1.10.

Psychologist Shane Frederick built a famous three-question test around this exact trap (a bat and a ball in the original), and at Harvard, MIT, and Princeton most students grabbed the fast, wrong answer. We're calling the move The Candy Trap: the answer that arrives instantly and feels obvious is the one you check first.

The check costs three seconds. The next 12 riddles are your training ground, and turkey timing and pie math keep the season going once the costumes come down, with two islanders who cannot both be lying waiting for a night with no candy in it.

Round one: Halloween math riddles

Six riddles, numbers included, a Candy Trap inside each. The candy poll up top was riddle 1, so we pick up at 2. Think first, then peek, and count your clean solves: the scoreboard at the end will ask.

Riddle 2 of 13

Gus buys a jack-o'-lantern for $8, sells it for $9, buys it back for $10, and sells it again for $11. How much profit does Gus make?

Riddle 3 of 13

Five witches brew five potions in five minutes. How long do a hundred witches need to brew a hundred potions?

Riddle 4 of 13

A vampire colony doubles every night. In 48 nights it fills the whole crypt. How many nights does it take to fill half the crypt?

Riddle 5 of 13

🎃 + 🎃 + 🎃 = 30🎃 + 🦇 + 🦇 = 20🦇 + 👻 = 10👻 + 🎃 × 🦇 = ?

Riddle 6 of 13

When Gretchen was 6, her little brother was half her age. This Halloween she turns 40. How old is her brother?

Riddle 7 of 13

The candy bowl holds chocolate eyeballs and gummy worms, plenty of both. The lights go out. How many candies must you grab to be sure you have two of the same kind?
Heron
Six down. But the arithmetic was the easy part: a sum warns you that a trap is coming. Round two puts the arithmetic away and fights dirty.

Round two: Halloween riddles for adults who feel safe now

The classics, with the safety off. No numbers left to warn you: from here, the trap always hides in the wording.

Riddle 8 of 13

In the costume race, you overtake the runner in second place. What place are you in now?

Riddle 9 of 13

Midnight in the haunted house. You have one match, a candle, an oil lamp, and a fireplace. What do you light first?

Riddle 10 of 13

A rooster lays an egg on the very peak of the witch's crooked roof. Which way does the egg roll?

Riddle 11 of 13

Some months have 31 days, some have 30. How many months have 28 days?

Riddle 12 of 13

How many candies can you put into an empty trick-or-treat bag?

Riddle 13 of 13

The more you take, the more you leave behind. You'll do it all the way through the graveyard tonight. What am I?

What to remember

Heron
  • The instant answer is a suspect. Question it before you say it out loud.
  • Check backwards. Plug your answer into the story: The Candy Trap dies in one line of arithmetic.
  • Traps love a party. Round numbers, rhymes, and costumes exist to make you rush. Slow is sharp.

Honest scoreboard: how many did you solve without peeking?

FAQ

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