Skip to main content

Can you solve the giant iron riddle? - Alex Gendler

  • 2,453,492 Views
  • 5,983 Questions Answered
  • TEDEd Animation

Let’s Begin…

The family of giants you work for is throwing a fancy dinner party, but there’s a problem — the elder giant’s favorite shirt is wrinkled! To fix it, you’ll need to power up the giant iron. It needs two batteries to work, but the baby giant mixed the working battery pile with the dead pile. Can you test the batteries so that you get a working pair in seven tries or less? Alex Gendler shows how.


Customize this lesson203

Create and share a new lesson based on this one.

About TED-Ed Animations

TED-Ed Animations feature the words and ideas of educators brought to life by professional animators. Are you an educator or animator interested in creating a TED-Ed Animation? Nominate yourself here »

Meet The Creators

  • Educator Alex Gendler
  • Director Outis
  • Narrator Addison Anderson
  • Animator Nemanja Petrovic
  • Sound Designer Nemanja Petrovic
  • Content Producer Gerta Xhelo
  • Editorial Producer Alex Rosenthal
  • Associate Producer Bethany Cutmore-Scott
  • Fact-Checker Brian Gutierrez
Additional Resources for you to Explore
This problem uses a formula known as the binomial coefficient to calculate how many ways there are to choose a given number of objects from a larger set, assuming that their order doesn’t matter. For more information, you can read about the binomial coefficient, the binomial theorem, and Pascal’s Triangle.

Customize this lesson

Create and share a new lesson based on this one.

About TED-Ed Animations

TED-Ed Animations feature the words and ideas of educators brought to life by professional animators. Are you an educator or animator interested in creating a TED-Ed Animation? Nominate yourself here »

Meet The Creators

  • Educator Alex Gendler
  • Director Outis
  • Narrator Addison Anderson
  • Animator Nemanja Petrovic
  • Sound Designer Nemanja Petrovic
  • Content Producer Gerta Xhelo
  • Editorial Producer Alex Rosenthal
  • Associate Producer Bethany Cutmore-Scott
  • Fact-Checker Brian Gutierrez

More from Math In Real Life