What do you pay?

The costume on the rack is $40.

The sign over the rack says 50% off.

Your coupon takes another 20% off.

What does the costume cost you in dollars at the register? Lock in your gut answer.

← BlogSep 11, 20262 min read

15 Halloween trivia questions you can work out at the party

Heron

I'm Heron. I wear a flamingo costume every Halloween, and I once bought it half off, handed over a 20% coupon, and told the cashier my savings were 70%.

So these fifteen questions are the ones a party can actually answer. Every one of them is solvable from the numbers printed inside it.

Why the $40 costume rings up at $16

Two discounts stack, and stacking is smaller than adding. The sign halves $40 and leaves $20, then the coupon takes a fifth of that $20, which is $4.

We're calling that move The Second Cut. Every discount after the first one measures itself against what is still on the tag, and the tag keeps shrinking.

The pair comes to 60% off the ticket, and swapping the order of the two cuts changes nothing. Let's run the same move on a meaner sign, one step at a time.

Step 1 of 5on the ticket

$60

Halloween trivia questions for the party

Seven questions, and every number you need is printed in them. The costume was number 1, so the cards start at 2, and the scoreboard at the end will ask how many you took clean. A month later the dinner table gets fifteen questions with the numbers baked in, and they play by this same rule.

Riddle 2 of 15

You buy 4 bags of 45 candies and hand out 3 to every kid. How many kids before the bowl is empty?

Riddle 3 of 15

Trick-or-treating runs 6:00 to 7:30, and each house takes 3 minutes. How many houses do you get to?

Riddle 4 of 15

Your sister comes home with three times your haul. Together you have 84 candies. How many are yours?

Riddle 5 of 15

A 20-pack of candy costs $6 and a 50-pack costs $12.50. Which one is cheaper per candy?

Riddle 6 of 15

Halloween falls on a Saturday, and the February that follows has 28 days. What day is it a year later?

Riddle 7 of 15

The horror marathon starts at 8:15 pm and runs three 95-minute movies back to back. When does it end?

Riddle 8 of 15

You need 240 candies for the porch and each bag holds 18. How many bags do you buy?

Question 5 is the one that follows you out of October. Price per unit is the only honest way to rank two bags, and the aisle is built to make you rank them by the number on the front, the way a 25% sign on a sweater does in our Christmas trivia questions.

One more sign before the wording turns mean, and this time you do it.

$50 − 20% − 25% =

Same rules as above. You've got this.

Heron

The next seven barely need a calculator. Six of them hide the whole difficulty in one word, and the last one hands the costume trick back to you wearing a different mask.

Read these out loud. A sentence does its best work on a room that is only half listening.

Halloween trivia questions that hide the trick in the wording

Every one of these is a reading test wearing a costume. The numbers are small enough to do standing up, and the wrong answer is usually the question you thought you heard.

The fix is to name the thing being asked for, out loud, before answering. A pound, a fraction of a room, a place in a line: each one is a different noun, and the noun is where the money is.

Question 9 collapses that way in about two seconds, and so does the bag that weighs 25% more. Let's slow the reading down and let the arithmetic take care of itself.

Riddle 9 of 15

You are third from the front of the candy line and third from the back. How many kids are in the line?

Riddle 10 of 15

Which weighs more: a pound of candy corn or a pound of plastic spider rings?

Riddle 11 of 15

A mummy is 3,000 years old. A vampire is twice as old as the mummy was 1,000 years ago. How old is the vampire?

Riddle 12 of 15

Half your guests come as ghosts. Half of the rest come as vampires. What fraction comes as neither?

Riddle 13 of 15

The party starts at 9:00 pm on the night the clocks go back an hour. How long until 3:00 am?

Riddle 14 of 15

Your candy bag weighs 4 pounds and your sister's is 25% heavier. How much lighter is yours than hers?

Riddle 15 of 15

Parents take a 10% candy tax, then you trade away 10% of what is left. How much of the haul survives?

All fifteen pay the same wage: the answer that turns up before the arithmetic does. The 70% that flashed into view at the costume rack is the cleanest example of it on this page.

Psychologist Shane Frederick built a famous three-question test around answers that arrive that fast, and at Harvard, MIT, and Princeton most students grabbed the fast, wrong answer. Our Halloween riddles call the reflex The Candy Trap, and it turns out to work in a costume aisle as happily as it does in a candy bowl.

What to remember

Heron
  • Percentages never add up. The Second Cut works on sale racks, tips, and salary offers, and Halloween is simply where it shows up in a costume.
  • Ask what the number is measured against. A quarter heavier one way is a fifth lighter the other, and both sentences describe the same pound.
  • Count yourself exactly once. Lines, shares, and rooms all hide the same double count, and drawing it once kills it.

Honest tally: how many did you solve without peeking?

FAQ

Trivia3 min read40 trivia questions and answers, all worked outEvery list hands you the answer on the same line, so your eye beats your brain to it. Forty questions in five rounds, with each answer covered until you commit.Trivia2 min readTrivia in three rounds, tiebreaker and allTen questions to play right now: a numbers round, a words round, and the tiebreaker where a stated assumption beats a shouted number.Trivia3 min readTrivia questions where the answer is printed inside the questionMost trivia nights are a memory test, and half the table is out before round two. Fifteen questions that need nothing you were supposed to have read.Riddles3 min readRiddles for kids, sorted by age, with a hint before the answerMost of us count the dogs, the cats, and the ducks, then leave our own two legs out of it. Thirteen riddles for kids, six per age band, hints on every card.Formulas2 min readThe arithmetic sequence formula and the minus one inside itRow 10 sits nine jumps behind row 1, and most of us multiply by ten. The formula, the sum, and a one-second test that catches the slip.Riddles3 min read25 riddles with answers where the answer is the cheap partThree ducks answer all three lines at once, and most of us add the lines up to five. Twenty-five riddles with answers, plus the move behind each.Riddles3 min read30 hard riddles for adults where knowing more hurtsA hole hands you three measurements and every one of them is honest. Thirty riddles with answers, and the reason the wrong one felt right.Times tables3 min readMultiplication strategies: five moves and when to use eachFive moves cover the whole chart, and a second move checks the first. 8 × 9 comes out 72 three different ways, plus nine questions to practice.Times tables3 min readThe 6 times table: five of them plus one moreSix is five plus one, so 6 × 8 is 40 plus 8. The table to 12, the four answers the trick writes out for you, and where the shortcut stops.Times tables3 min readThe 9 times table: ten of them, minus oneNine is ten minus one, so 9 × 6 is 60 take away 6. The table to 12, why the finger trick works, and the five facts that need learning.Times tables3 min readThe 12 times table: ten of them plus two moreA dozen is ten plus two, so 12 × 9 is 90 plus 18. The table to 12, the split, and the one fact on it you have not met before.Times tables3 min readThe 3 times table: the number plus its doubleThree is two plus one, so 3 × 9 is 9 plus 18. The table to 12, the trick, and a digit check that catches a wrong answer.Times tables3 min readThe 4 times table: double it twiceFour is two twos, so 4 × 9 is 9 doubled twice. The table to 12, the two doubles, and ten questions to practice.Times tables3 min readThe multiplication tables check: six seconds a questionTwenty-five questions, six seconds each, and the limit was chosen so working it out does not fit. The format and ten questions to practice.Times tables3 min readThe 7 times table: five plus twoSeven is five and two, so 7 × 8 is 40 plus 16. The table to 12, the split, and ten questions to practice.Times tables3 min readThe 8 times table: double, double, doubleEight is two doubled twice, so 8 × 7 is 7 doubled three times. The table to 12, the trick, and ten questions to practice.Riddles3 min read13 Christmas riddles you can solve at the tableA stable with 14 heads and 40 legs, a tree an inch too tall for the ceiling, and a package that lands four seats short.Trivia2 min read12 Christmas trivia questions with the math inside themThe song hands over 364 gifts, a Secret Santa saves 48 of them, and the twelfth day lands earlier than the table thinks.Logic3 min read12 logic puzzles that make you prove itTwo islanders who cannot both be lying, a drinks grid that fills itself in, and four cards that hide the only two worth turning.Riddles2 min read13 Thanksgiving riddles the whole table can solveA bread basket that empties on the third guest, three card tables that lose four seats, and a Christmas that shows up early.Trivia2 min read15 Thanksgiving trivia questions for the tableA bird that has to be in the oven by 1:30, two pies among seven people, and a pie that is more than twice the pie.Puzzles3 min read30 math puzzles where the fast answer is wrongEight balls and one balance scale, a log that needs five cuts, and a room where 99% turns out to be a single person.Paradoxes3 min readThe Monty Hall problem: switch, and you win twice as oftenPlay the three-door game from the movie 21, then see why switching wins 2 times in 3, and the line Ben brushed off.Riddles3 min read11 math riddles that fool smart adultsA snail in a well, a missing dollar, and a brick that weighs itself. The numbers lie first, the wording lies second.Riddles3 min read13 Halloween riddles that trick your brainCandy-math traps, doubling vampires, and classic trick questions. Six warm-ups, then the mean ones.Viral math3 min read8÷2(2+2) = ? The viral equation that broke the internetHalf the internet picked a side. Both camps have a point, and the real villain has been hiding in plain sight.