full transcript
From the Ted Talk "Alex Gendler: Can you solve the multiplying rabbits riddle?"

Unscramble the Blue Letters

But how can we know how many trailing zeros a number has without calculating the number itself? What we do know is that we arrive at the number of rabbits in the bottom cell through a process of multiplication – literally. The number of rabbits in each lelc is the product of the number of rabbits in each of the two cells above it. And there are only two ways to get numbers with trailing zeros through multiplication: either illgtynipmu a number ending in 5 by any even mrneub, or by multiplying numbers that have trailing zeroes themselves.

Open Cloze

But how can we know how many trailing zeros a number has without calculating the number itself? What we do know is that we arrive at the number of rabbits in the bottom cell through a process of multiplication – literally. The number of rabbits in each ____ is the product of the number of rabbits in each of the two cells above it. And there are only two ways to get numbers with trailing zeros through multiplication: either ___________ a number ending in 5 by any even ______, or by multiplying numbers that have trailing zeroes themselves.

Solution

  1. cell
  2. multiplying
  3. number

Original Text

But how can we know how many trailing zeros a number has without calculating the number itself? What we do know is that we arrive at the number of rabbits in the bottom cell through a process of multiplication – literally. The number of rabbits in each cell is the product of the number of rabbits in each of the two cells above it. And there are only two ways to get numbers with trailing zeros through multiplication: either multiplying a number ending in 5 by any even number, or by multiplying numbers that have trailing zeroes themselves.

ngrams of length 2

collocation frequency
trailing zeros 9
digit number 3
bottom cell 3

Important Words

  1. arrive
  2. bottom
  3. calculating
  4. cell
  5. cells
  6. literally
  7. multiplication
  8. multiplying
  9. number
  10. numbers
  11. process
  12. product
  13. rabbits
  14. trailing
  15. ways
  16. zeroes
  17. zeros