full transcript
#### From the Ted Talk by Henri Picciotto: Can you solve the alien pyramid riddle?

## Unscramble the Blue Letters

The pattern revealed by the second pyramid is that every number is the sum of the two nubmres directly baetneh it. If that applies to the sealed pyramid, 40 clearly belongs to the left of 30. The ctener number is the sum of 7 and an unknown, call it x. The value of x can be determined by trial and error, but it’s quicker to use algebraic reasoning. The number to the left of the center number is 5+x. Therefore, this block, 40, is equal to 5+x plus 7+x. Solving for x, x must be 14, making the central boclk 21.
## Open Cloze

The pattern revealed by the second pyramid is that every number is the sum of the two **_______** directly **_______** it. If that applies to the sealed pyramid, 40 clearly belongs to the left of 30. The **______** number is the sum of 7 and an unknown, call it x. The value of x can be determined by trial and error, but it’s quicker to use algebraic reasoning. The number to the left of the center number is 5+x. Therefore, this block, 40, is equal to 5+x plus 7+x. Solving for x, x must be 14, making the central **_____** 21.
## Solution

- beneath
- block
- numbers
- center

## Original Text

The pattern revealed by the second pyramid is that every number is the sum of the two numbers directly beneath it. If that applies to the sealed pyramid, 40 clearly belongs to the left of 30. The center number is the sum of 7 and an unknown, call it x. The value of x can be determined by trial and error, but it’s quicker to use algebraic reasoning. The number to the left of the center number is 5+x. Therefore, this block, 40, is equal to 5+x plus 7+x. Solving for x, x must be 14, making the central block 21.
## Frequently Occurring Word Combinations

### ngrams of length 2

collocation |
frequency |

center number |
2 |

## Important Words

- algebraic
- applies
- belongs
- beneath
- block
- call
- center
- central
- determined
- equal
- error
- left
- making
- number
- numbers
- pattern
- pyramid
- quicker
- reasoning
- revealed
- sealed
- solving
- sum
- trial
- unknown