full transcript
#### From the Ted Talk by Judd A. Schorr: Can you solve the airplane riddle?

## Unscramble the Blue Letters

Professor Fukanō, the famous eccentric scientist and adventurer, has ekermbad on a new challenge: flying around the wlrod nonstop in a plane of his own design. Able to travel cinlnossetty at the incredible speed of one degree longitude around the eqtouar per minute, the plane would take six hours to circle the world. There's just one problem: the plane can only hold 180 kiloliters of fuel, only enough for exactly half the jruenoy. Let's be hnoest. The professor probably could have designed the plane to hold more fuel, but where's the fun in that? Instead, he's devised a slightly more eorltabae solution: building three identical planes for the mission. In addition to their speed, the professor's eupepiqd them with a few other incredible features. Each of the planes can turn on a dime and instantly transfer any amount of its fuel to any of the others in midair without snoiwlg down, provided they're next to each other. The professor will pilot the first plane, while his two assistants Fugōri and Orokana will pilot each of the others. However, only one airport, located on the equator, has gntared posiresmin for the eeminxeprt, making it the starting point, the finish line, and the only spot where the planes can land, takeoff, or refuel on the grnuod. How should the three planes coordinate so the professor can fly cionuslnuoty for the whole trip and achieve his dream without anyone rnunnig out of fuel and crashing? Pause here if you want to figure it out for yourself. Answer in: 3 awsenr in: 2 Answer in: 1 According to the professor's calculations, they should be able to pull it off by a hair. The key is to maximize the support each assistant provides, not wasting a single kiloliter of fuel. It also helps us to think symmetrically so they can make shorter trips in either direction while setting the professor up for a long unsupported stretch in the mdlide. Here's his solution. All three planes take off at noon flying west, each fully loaded with 180 kiloliters. After 45 minutes, or one-eighth of the way around, each pnale has 135 kiloliters left. Orokana gives 45 to the professor and 45 to Fugōri, fully rfulineeg them both. With her remaining 45, Orokana returns to the airport and heads to the lounge for a well-deserved braek. 45 minutes later, with one-quarter of the trip complete, the professor and frugōi are both at 135 kltiroiles again. Fugōri transfers 45 into the professor's tank, leaving himself with the 90 he needs to return. pefsrosor Fukanō stretches and puts on his favorite album. He'll be alone for a while. In the meantime, Orokana has been asxnluoiy awaiting Fugōri's return, her plane fully refueled and ready to go. As soon as his plane touches the ground, she taeks off, this time flying east. At this point, exactly 180 minutes have pseasd and the professor is at the halfway point of his journey with 90 kiloliters of fuel left. For the next 90 mtinues, the professor and Orokana's planes fly towards each other, meeting at the three-quarter mark. Just as the professor's fuel is about the run out, he sees Orokana's plane. She gives him 45 kiloliters of her remaining 90, leaving them with 45 each. But that's just half of what they need to make it to the airport. felrnuatoty, this is exactly when Fugōri, having rfleeued, takes off. 45 minutes later, just as the other two planes are about to run empty, he mtees them at the 315 degree point and transfers 45 kiloliters of fuel to each, leaving 45 for himself. All three planes land at the airport just as their fuel gauges reach zero. As the reporters and photographers cheer, the professor promises his planes will soon be available for commercial flights, just as soon as they figure out how to keep their inflight mlaes from spilling everywhere.
## Open Cloze

Professor Fukanō, the famous eccentric scientist and adventurer, has **________** on a new challenge: flying around the **_____** nonstop in a plane of his own design. Able to travel **____________** at the incredible speed of one degree longitude around the **_______** per minute, the plane would take six hours to circle the world. There's just one problem: the plane can only hold 180 kiloliters of fuel, only enough for exactly half the **_______**. Let's be **______**. The professor probably could have designed the plane to hold more fuel, but where's the fun in that? Instead, he's devised a slightly more **_________** solution: building three identical planes for the mission. In addition to their speed, the professor's **________** them with a few other incredible features. Each of the planes can turn on a dime and instantly transfer any amount of its fuel to any of the others in midair without **_______** down, provided they're next to each other. The professor will pilot the first plane, while his two assistants Fugōri and Orokana will pilot each of the others. However, only one airport, located on the equator, has **_______** **__________** for the **__________**, making it the starting point, the finish line, and the only spot where the planes can land, takeoff, or refuel on the **______**. How should the three planes coordinate so the professor can fly **____________** for the whole trip and achieve his dream without anyone **_______** out of fuel and crashing? Pause here if you want to figure it out for yourself. Answer in: 3 **______** in: 2 Answer in: 1 According to the professor's calculations, they should be able to pull it off by a hair. The key is to maximize the support each assistant provides, not wasting a single kiloliter of fuel. It also helps us to think symmetrically so they can make shorter trips in either direction while setting the professor up for a long unsupported stretch in the **______**. Here's his solution. All three planes take off at noon flying west, each fully loaded with 180 kiloliters. After 45 minutes, or one-eighth of the way around, each **_____** has 135 kiloliters left. Orokana gives 45 to the professor and 45 to Fugōri, fully **_________** them both. With her remaining 45, Orokana returns to the airport and heads to the lounge for a well-deserved **_____**. 45 minutes later, with one-quarter of the trip complete, the professor and **______** are both at 135 **__________** again. Fugōri transfers 45 into the professor's tank, leaving himself with the 90 he needs to return. **_________** Fukanō stretches and puts on his favorite album. He'll be alone for a while. In the meantime, Orokana has been **_________** awaiting Fugōri's return, her plane fully refueled and ready to go. As soon as his plane touches the ground, she **_____** off, this time flying east. At this point, exactly 180 minutes have **______** and the professor is at the halfway point of his journey with 90 kiloliters of fuel left. For the next 90 **_______**, the professor and Orokana's planes fly towards each other, meeting at the three-quarter mark. Just as the professor's fuel is about the run out, he sees Orokana's plane. She gives him 45 kiloliters of her remaining 90, leaving them with 45 each. But that's just half of what they need to make it to the airport. **___________**, this is exactly when Fugōri, having **________**, takes off. 45 minutes later, just as the other two planes are about to run empty, he **_____** them at the 315 degree point and transfers 45 kiloliters of fuel to each, leaving 45 for himself. All three planes land at the airport just as their fuel gauges reach zero. As the reporters and photographers cheer, the professor promises his planes will soon be available for commercial flights, just as soon as they figure out how to keep their inflight **_____** from spilling everywhere.
## Solution

- journey
- slowing
- equator
- refueling
- fortunately
- meals
- equipped
- elaborate
- honest
- refueled
- meets
- embarked
- fugōri
- answer
- experiment
- break
- takes
- granted
- permission
- plane
- running
- kiloliters
- professor
- consistently
- ground
- continuously
- minutes
- world
- middle
- anxiously
- passed

## Original Text

Professor Fukanō, the famous eccentric scientist and adventurer, has embarked on a new challenge: flying around the world nonstop in a plane of his own design. Able to travel consistently at the incredible speed of one degree longitude around the equator per minute, the plane would take six hours to circle the world. There's just one problem: the plane can only hold 180 kiloliters of fuel, only enough for exactly half the journey. Let's be honest. The professor probably could have designed the plane to hold more fuel, but where's the fun in that? Instead, he's devised a slightly more elaborate solution: building three identical planes for the mission. In addition to their speed, the professor's equipped them with a few other incredible features. Each of the planes can turn on a dime and instantly transfer any amount of its fuel to any of the others in midair without slowing down, provided they're next to each other. The professor will pilot the first plane, while his two assistants Fugōri and Orokana will pilot each of the others. However, only one airport, located on the equator, has granted permission for the experiment, making it the starting point, the finish line, and the only spot where the planes can land, takeoff, or refuel on the ground. How should the three planes coordinate so the professor can fly continuously for the whole trip and achieve his dream without anyone running out of fuel and crashing? Pause here if you want to figure it out for yourself. Answer in: 3 Answer in: 2 Answer in: 1 According to the professor's calculations, they should be able to pull it off by a hair. The key is to maximize the support each assistant provides, not wasting a single kiloliter of fuel. It also helps us to think symmetrically so they can make shorter trips in either direction while setting the professor up for a long unsupported stretch in the middle. Here's his solution. All three planes take off at noon flying west, each fully loaded with 180 kiloliters. After 45 minutes, or one-eighth of the way around, each plane has 135 kiloliters left. Orokana gives 45 to the professor and 45 to Fugōri, fully refueling them both. With her remaining 45, Orokana returns to the airport and heads to the lounge for a well-deserved break. 45 minutes later, with one-quarter of the trip complete, the professor and Fugōri are both at 135 kiloliters again. Fugōri transfers 45 into the professor's tank, leaving himself with the 90 he needs to return. Professor Fukanō stretches and puts on his favorite album. He'll be alone for a while. In the meantime, Orokana has been anxiously awaiting Fugōri's return, her plane fully refueled and ready to go. As soon as his plane touches the ground, she takes off, this time flying east. At this point, exactly 180 minutes have passed and the professor is at the halfway point of his journey with 90 kiloliters of fuel left. For the next 90 minutes, the professor and Orokana's planes fly towards each other, meeting at the three-quarter mark. Just as the professor's fuel is about the run out, he sees Orokana's plane. She gives him 45 kiloliters of her remaining 90, leaving them with 45 each. But that's just half of what they need to make it to the airport. Fortunately, this is exactly when Fugōri, having refueled, takes off. 45 minutes later, just as the other two planes are about to run empty, he meets them at the 315 degree point and transfers 45 kiloliters of fuel to each, leaving 45 for himself. All three planes land at the airport just as their fuel gauges reach zero. As the reporters and photographers cheer, the professor promises his planes will soon be available for commercial flights, just as soon as they figure out how to keep their inflight meals from spilling everywhere.
## Frequently Occurring Word Combinations

## Important Words

- achieve
- addition
- adventurer
- airport
- album
- amount
- answer
- anxiously
- assistant
- assistants
- awaiting
- break
- building
- calculations
- cheer
- circle
- commercial
- complete
- consistently
- continuously
- coordinate
- crashing
- degree
- design
- designed
- devised
- dime
- direction
- dream
- east
- eccentric
- elaborate
- embarked
- empty
- equator
- equipped
- experiment
- famous
- favorite
- features
- figure
- finish
- flights
- fly
- flying
- fortunately
- fuel
- fugōri
- fukanō
- fully
- fun
- gauges
- granted
- ground
- hair
- halfway
- heads
- helps
- hold
- honest
- hours
- identical
- incredible
- inflight
- instantly
- journey
- key
- kiloliter
- kiloliters
- land
- leaving
- left
- line
- loaded
- located
- long
- longitude
- lounge
- making
- mark
- maximize
- meals
- meeting
- meets
- midair
- middle
- minute
- minutes
- mission
- nonstop
- noon
- orokana
- passed
- pause
- permission
- photographers
- pilot
- plane
- planes
- point
- professor
- promises
- pull
- puts
- reach
- ready
- refuel
- refueled
- refueling
- remaining
- reporters
- return
- returns
- run
- running
- scientist
- sees
- setting
- shorter
- single
- slightly
- slowing
- solution
- speed
- spilling
- spot
- starting
- stretch
- stretches
- support
- symmetrically
- takeoff
- takes
- tank
- time
- touches
- transfer
- transfers
- travel
- trip
- trips
- turn
- unsupported
- wasting
- west
- world