Did you solve it? Interview questions for aspiring billionaires | Science

Earlier today I have put you three puzzles that were corresponding questions in PayPal, an online payment company run by a group of billionaire technology – Elon Musk, Pter Thiel and David Sacks – now known as the right -wing policy. Here they are again with solutions.

1. Divide and oppress

Complete numbers either have an individual number of unique divisions or my husband’s number. What are the full numbers that have an individual number of divisions?

[A divisor of Z is a number that divides into Z. For example, the divisors of 24 are 1, 2, 3, 4, 6, 8, 12, 24. There are thus eight unique divisors of 24.]

solution: Square numbers: 1, 4, 9, 16, 25, …

Evidence of outline: Let Z is a full number, and D is divided into Z. = 2, then D* = 12.

We can pair each division D with a complement D*. All full numbers have an equal number of divisions, unless The square number, because in this case there is divided by D = D*. The question posed by the unique divisions. If D = D*, we consider D only once when calculating Divosors. Thus, the total number of divisions for the square number will be an equal number + 1, that is, a strange number.

2. Rabb

There are two ropes, each of which differs density along its length, so that it burns at different rates at different locations along its lengths, but each takes one hour for the entire burning. How can you use ropes to measure 45 minutes?

solution: Each ends one strap, and one end of the other at the same time. The ends of the burnt cord will meet from the first cord after half an hour. At this moment, there will be half an hour the left of the burning on the second cord, so the second end shines. When the ends of the second cord of the second cord meet to another 15 minutes, you will get a total of 45 minutes from the start.

3

There is a circular schedule of an unspecified diameter. You and your opponent have supplies of symmetrical coins. The game is for you to put a coin on the table in turn. No currency can be transferred after its placement and no currency can be fully or partially placed on top of another. The first player is unable to put the currency to lose. What is your strategy to ensure your victory?

solution:

You go first and put a coin in the middle of the table. When your opponent places a coin on the table, you put it in the position completely opposite (i.e. rotating 180 degrees around the center of the table). There will always be space in this position. In the end, your opponent will run out of space.

These puzzles are brief from Founders Written by Jimmy Sony, a book on the PayPal – BROS technology associated with the online payment company.

I hope you enjoyed my puzzles today. I will return within two weeks.

I have prepared a mystery here on Mondays since 2015. I have always been aware of the wonderful puzzles. If you want one suggestion, Send me.