Can you solve the birthday cake riddle? - Marie Brodsky

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Your friend’s birthday is tomorrow, and he’s turning… well… you’ve forgotten. A ginormous cake has been prepared and your job is to sculpt his age as the chocolate centerpiece. The birthday boy is a giant, and you’re afraid that if your forgetfulness becomes known, you’ll become part of the feast. Can you figure out your friend’s age before the party? Marie Brodsky shows how.

Lesson by Marie Brodsky, directed by Igor Coric, Artrake Studio.

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[samcarpenter]

The real riddle here is why I keep hanging out with giants who can and will eat me for minor things.

[globingoblin]

The giant waking up after a nightmare and seeing the candles on his cake turn themselves on and off 👁️👄👁️

[teamcyeborg]

Honestly immediate brute-force strategy was to go through and turn off every candle that you come across until you stop coming across lit ones. Pick a random spot and light it; Now go loop around and count the candles until you see a lit one. Turn it off (and/or turn on the two around it, or some other pattern to mark it off) and circle back around the same number of candles. If it changed, you've got his age.

[Jgaldragon]

You could also ask the giant or any tall guest to lift you up to get a better view of the candles. You can tell them you wanted to see how big of a centerpiece you could make with the space available.

[joaobello]

I love when they pause the riddle to show you the rules, rule number 5 says not to take your clothes off, because is unsanitary and basically tells everyone off because that would probably be an option 😂😂😂

[OzziePerez]

I would just ask the baker since he's the one that installed on the candles 😂

[spodreman]

Answers I think should be possible:
1. You should have some sense of where you started, based on the path you took to enter the cake’s interior. Start counting from there until you reach that starting point again.
2. Ask the baker if he/she put enough candles on the cake, keep asking until they unknowingly give away the age.
3. Verify you have green eyes, then leave the giant’s house.

[jeconiahjoelmichaelsiregar]

I like how at 4:26 there's objects from other riddles getting blown away with us like the elemental crystals (Fire Crystal riddle), the fabergé egg (Egg Drop riddle), and the gold and silver Tri-source hexagons as well as the gems (Dongle's Difficult Dilemma)

[sarahcunha]

plot twist: The giant baker guessed the giant's age and didn't put the right amount of candles on the cake

[jaromtoy]

I’m a little confused - what’s preventing us from walking around the cake, turning off all the candles until we go for a while without lit candles (supposing he’s timeless and we have no way of being sure of his age), then lighting one and counting the candles all the way around until you get back to the start?

Aka, turn all the candles off then count them starting from one candle that you turn on?

[kaylenvee]

Can you imagine if the giant woke up in the middle of the night just to see the candles flickering on and off on their own? You'd never have to worry for time because he wouldn't want to eat that cake anymore.

[terabyte]

My idea was turning off all candles and checking periodically outside if any candles are casting light. Then going one direction and counting while turning them all on. The first one I see on means I've made a loop

[theothers]

Oh, just ask the baker how many candles did he put. If you're afraid of being found out that you didn't remember the age, ask a tricky question to let him spill how many candles are there (or the age).

[clayel]

Rule 5. “…No removing your clothing either. That’s unsanitary. This is food, people.” damn, they knew what we were gonna think of

[INTstincts]

Alternate solution which feels like cheating, but is never called out as being illegal by the rules:

Walk around and turn every candle you see off. After some time, exit the cake and see if the room is dark. If not, enter the cake again and keep turning off candles, checking again periodically. If it is, you have turned off every candle, and can re-enter the cake and turn one candle on, then walk the loop until you reach your lit candle.

This gives you a definite state you can check for without having to backtrack or make too many additional loops

[lilmarionscorner]

1:25 Rule 5 reads: "You are carrying nothing with you, and any marks you make will dissapear. No removing your clothing either. That's unsanitary. This is food, people."

[TakeruTakashi]

I think that the morale is clear enough: dont make chocolate ornaments for someone who could eat you for not remembering its age

[echojr.]

Solving one of these Ted-Ed riddles on my own is on my bucket list

[mcipher]

Easier solution: You can’t leave marks on the cake but you can leave marks on the candle, grab a piece of cake and draw with it a distinct letter or symbol on the surface of the candle, now just count the candles and no matter their state, you’ll always arrive to your marked candle, thus doing only one loop.

[ChaunceyBeggs]

Wouldn't it be more efficient to use prime numbers for your initial guesses? That way you don't need to worry about factors as possibilities. Also, by turning on all candles from the beginning, you can quickly determine if the actual amount is less than your guess (you run into an unlit candle earlier than expected while backtracking) or greater.