full transcript
From the Ted Talk "Alex Gendler: Can you solve the giant iron riddle?"

#### Unscramble the Blue Letters

So instead of six batteries, let’s take any three. This group has a total of three possible combinations. Since both batteries have to be working for the iron to power up, a liegsn failure can’t tell you whether both batteries are dead, or just one. But if all three combinations fail, then you’ll know this group has either one good battery, or none at all. Now you can set those three aside and repeat the process for another three raiebtste. You might get a match, but if every combination fails again, you’ll know this set can have no more than one good battery. That would leave only two batteries untried. Since there are four good batteries in latto and you’ve only dauoccnte for two so far, both of these minerngia ones must be good.

#### Open Cloze

So instead of six batteries, let’s take any three. This group has a total of three possible combinations. Since both batteries have to be working for the iron to power up, a ______ failure can’t tell you whether both batteries are dead, or just one. But if all three combinations fail, then you’ll know this group has either one good battery, or none at all. Now you can set those three aside and repeat the process for another three _________. You might get a match, but if every combination fails again, you’ll know this set can have no more than one good battery. That would leave only two batteries untried. Since there are four good batteries in _____ and you’ve only _________ for two so far, both of these _________ ones must be good.

1. batteries
2. total
3. accounted
4. single
5. remaining

#### Original Text

So instead of six batteries, let’s take any three. This group has a total of three possible combinations. Since both batteries have to be working for the iron to power up, a single failure can’t tell you whether both batteries are dead, or just one. But if all three combinations fail, then you’ll know this group has either one good battery, or none at all. Now you can set those three aside and repeat the process for another three batteries. You might get a match, but if every combination fails again, you’ll know this set can have no more than one good battery. That would leave only two batteries untried. Since there are four good batteries in total and you’ve only accounted for two so far, both of these remaining ones must be good.

#### ngrams of length 2

collocation frequency
good batteries 3

#### Important Words

1. accounted
2. batteries
3. battery
4. combination
5. combinations
7. fail
8. fails
9. failure
10. good
11. group
12. iron
13. leave
14. match
15. power
16. process
17. remaining
18. repeat
19. set
20. single
21. total
22. untried
23. working