full transcript
#### From the Ted Talk by Lisa Winer: Can you solve the locker riddle?

## Unscramble the Blue Letters

Your rich, eicetrncc uncle just passed away, and you and your 99 nasty relatives have been invited to the rnadieg of his will. He wanted to laeve all of his money to you, but he knew that if he did, your relatives would pester you forever. So he is banking on the fact that he taught you everything you need to know about riddles. Your ulnce left the following note in his will: "I have certaed a puzzle. If all 100 of you answer it together, you will sahre the money evenly. However, if you are the first to find the prtaetn and solve the problem without going through all of the leg work, you will get the etrine itcenianhre all to yourself. Good luck." The lawyer takes you and your 99 relatives to a secret room in the mansion that contains 100 lockers, each hiding a single word. He explains: Every relative is assigned a neubmr from 1 to 100. Heir 1 will open every locker. Heir 2 will then close every second locker. Heir 3 will change the sttuas of every third locker, specifically if it's open, she'll clsoe it, but if it's closed, she'll open it. This pattern will continue until all 100 of you have gone. The words in the lockers that remain open at the end will help you cacrk the code for the safe. Before csuion Thaddeus can even start down the line, you step forward and tell the lawyer you know which lockers will remain open. But how? Pause the vdieo now if you want to figure it out for yourself! Answer in: 3 Answer in: 2 aesnwr in: 1 The key is realizing that the number of times a locker is touched is the same as the number of factors in the locker number. For example, in lekocr #6, Person 1 will open it, Person 2 will close it, Person 3 will open it, and Person 6 will close it. The numbers 1, 2, 3, and 6 are the factors of 6. So when a locker has an even number of factors it will remain closed, and when it has an odd number of factors, it will remain open. Most of the lockers have an even number of factors, which makes sense because factors naturally pair up. In fact, the only locreks that have an odd number of factors are pfreect squares because those have one foactr that when multiplied by itself equals the number. For Locker 9, 1 will open it, 3 will close, and 9 will open it. 3 x 3 = 9, but the 3 can only be counted once. Therefore, every locker that is a perfect square will remain open. You know that these ten lockers are the solution, so you open them immediately and read the wrods inside: "The code is the first five lockers touched only twice." You rleziae that the only lockers touched twice have to be pmrie numbers since each only has two factors: 1 and itself. So the code is 2-3-5-7-11. The lawyer brings you to the safe, and you claim your inheritance. Too bad your relatives were always too busy being nasty to each other to pay attention to your eccentric uncle's riddles.
## Open Cloze

Your rich, **_________** uncle just passed away, and you and your 99 nasty relatives have been invited to the **_______** of his will. He wanted to **_____** all of his money to you, but he knew that if he did, your relatives would pester you forever. So he is banking on the fact that he taught you everything you need to know about riddles. Your **_____** left the following note in his will: "I have **_______** a puzzle. If all 100 of you answer it together, you will **_____** the money evenly. However, if you are the first to find the **_______** and solve the problem without going through all of the leg work, you will get the **______** **___________** all to yourself. Good luck." The lawyer takes you and your 99 relatives to a secret room in the mansion that contains 100 lockers, each hiding a single word. He explains: Every relative is assigned a **______** from 1 to 100. Heir 1 will open every locker. Heir 2 will then close every second locker. Heir 3 will change the **______** of every third locker, specifically if it's open, she'll **_____** it, but if it's closed, she'll open it. This pattern will continue until all 100 of you have gone. The words in the lockers that remain open at the end will help you **_____** the code for the safe. Before **______** Thaddeus can even start down the line, you step forward and tell the lawyer you know which lockers will remain open. But how? Pause the **_____** now if you want to figure it out for yourself! Answer in: 3 Answer in: 2 **______** in: 1 The key is realizing that the number of times a locker is touched is the same as the number of factors in the locker number. For example, in **______** #6, Person 1 will open it, Person 2 will close it, Person 3 will open it, and Person 6 will close it. The numbers 1, 2, 3, and 6 are the factors of 6. So when a locker has an even number of factors it will remain closed, and when it has an odd number of factors, it will remain open. Most of the lockers have an even number of factors, which makes sense because factors naturally pair up. In fact, the only **_______** that have an odd number of factors are **_______** squares because those have one **______** that when multiplied by itself equals the number. For Locker 9, 1 will open it, 3 will close, and 9 will open it. 3 x 3 = 9, but the 3 can only be counted once. Therefore, every locker that is a perfect square will remain open. You know that these ten lockers are the solution, so you open them immediately and read the **_____** inside: "The code is the first five lockers touched only twice." You **_______** that the only lockers touched twice have to be **_____** numbers since each only has two factors: 1 and itself. So the code is 2-3-5-7-11. The lawyer brings you to the safe, and you claim your inheritance. Too bad your relatives were always too busy being nasty to each other to pay attention to your eccentric uncle's riddles.
## Solution

- number
- cousin
- answer
- status
- words
- uncle
- crack
- lockers
- created
- perfect
- video
- entire
- prime
- eccentric
- inheritance
- pattern
- leave
- reading
- factor
- close
- locker
- share
- realize

## Original Text

Your rich, eccentric uncle just passed away, and you and your 99 nasty relatives have been invited to the reading of his will. He wanted to leave all of his money to you, but he knew that if he did, your relatives would pester you forever. So he is banking on the fact that he taught you everything you need to know about riddles. Your uncle left the following note in his will: "I have created a puzzle. If all 100 of you answer it together, you will share the money evenly. However, if you are the first to find the pattern and solve the problem without going through all of the leg work, you will get the entire inheritance all to yourself. Good luck." The lawyer takes you and your 99 relatives to a secret room in the mansion that contains 100 lockers, each hiding a single word. He explains: Every relative is assigned a number from 1 to 100. Heir 1 will open every locker. Heir 2 will then close every second locker. Heir 3 will change the status of every third locker, specifically if it's open, she'll close it, but if it's closed, she'll open it. This pattern will continue until all 100 of you have gone. The words in the lockers that remain open at the end will help you crack the code for the safe. Before cousin Thaddeus can even start down the line, you step forward and tell the lawyer you know which lockers will remain open. But how? Pause the video now if you want to figure it out for yourself! Answer in: 3 Answer in: 2 Answer in: 1 The key is realizing that the number of times a locker is touched is the same as the number of factors in the locker number. For example, in locker #6, Person 1 will open it, Person 2 will close it, Person 3 will open it, and Person 6 will close it. The numbers 1, 2, 3, and 6 are the factors of 6. So when a locker has an even number of factors it will remain closed, and when it has an odd number of factors, it will remain open. Most of the lockers have an even number of factors, which makes sense because factors naturally pair up. In fact, the only lockers that have an odd number of factors are perfect squares because those have one factor that when multiplied by itself equals the number. For Locker 9, 1 will open it, 3 will close, and 9 will open it. 3 x 3 = 9, but the 3 can only be counted once. Therefore, every locker that is a perfect square will remain open. You know that these ten lockers are the solution, so you open them immediately and read the words inside: "The code is the first five lockers touched only twice." You realize that the only lockers touched twice have to be prime numbers since each only has two factors: 1 and itself. So the code is 2-3-5-7-11. The lawyer brings you to the safe, and you claim your inheritance. Too bad your relatives were always too busy being nasty to each other to pay attention to your eccentric uncle's riddles.
## Frequently Occurring Word Combinations

### ngrams of length 2

collocation |
frequency |

remain open |
4 |

locker heir |
2 |

odd number |
2 |

lockers touched |
2 |

## Important Words

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- specifically
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- times
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- word
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- work