Rumour has it that numerous tech powerhouses ask applicants to solve brain teasers and math problems during the interview process. It helps to distinguish those that can think creatively from those that don’t.
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Amazon, like Google, follows a similar process. Reports show that Amazon asks its applicants to solve a complicated problem, too. It’s called the ‘hanging cable challenge.’ Here’s the question:
'A cable of 80 meters is hanging from the top of two poles that are both 50 meters off the ground. What is the distance between the two poles—to one decimal point—if the centre cable is: 20 meters off the ground and 10 meters off the ground.'
We don’t know about you, but the first sentence alone hurts our brains. Google follows a similar format, but their question involves 25 horses and a race. Here it is:
'There are 25 horses. What is the minimum number of races needed so you can identify the fastest 3 horses? You can race up to 5 horses at a time, but you do not have a watch.'
Don’t worry. We’re just as confused as you. Thankfully, Presh Talwalkar explains the problem more in-depth on his blog, MindYourDecisions. Here’s the breakdown:
'There are 25 mechanical horses and a single racetrack. Each horse completes the track in a pre-programmed time, and the horses all have different finishing times, unknown to you. You can race 5 horses at a time. After a race is over, you get a printout with the order the horses finished, but not the finishing times of the horses. What is the minimum number of races you need to identify the fastest 3 horses?'
Um, what? We’ll give you a moment to try and solve the problem. Once you’re done, feel free to take a look at our video to see if you’ve calculated the right answer!
