Mark wrote,
MARCH
2.4142 km
RAY
12 (each time)
PURPLE
purple
At last the remaining answers you seek.
After 120 seconds, will the lamp (the "infinity machine") be on or off
>>> Indeterminant - This procedure never makes it to 120 seconds.
IQ solution to: The infinity machine - a Gedanken experiment
It is obvious that the addition of 60 + 30 + 15 + 7.5 + ... converges to the value of 120. The addition of all elements up to infinity in fact leads to 120. But if you did an infinite number of switches, every time the lamp is on, it has to be switched off immediately. On the other hand, every time the lamp is off, it has to be switched on immediately!
Therefore, at 120 seconds the lamp is either on and off, or neither on or off?!
If "0" means the lamp is off and "1" the lamp is on, we can calculate the sum of the switching operations:
(+1 for switch on, -1 for switch off)
+ 1 - 1 + 1 - 1 + 1 - 1 ....
After 120 seconds, there is no result; instead this infinite sequence oscillates between two values (0 and 1). That means were are able to determine the status of the lamp for every time point before 120 seconds, but not for 120 seconds (or later). This is simply because an infinite sequence does not have a last term.
In other words: It is true that the lamp has to be on or off after 120 seconds, but we are not able to find out which is the case!
A casino in Las Vegas: You want to join a game with three cards. One is white on both sides, one is red on both sides, and the third is white on one and red on the other side. Every card is in a black case. You have to chose one of these cases and pull out the card so you can see one side of the card.
Let's say the visible side of the card is white. The banker offers you a bet of 50:50 that the back side is also white.
Would you play this game?
>>> No - the probability of other side being white is 2/3
IQ solution to: Playing cards in Las Vegas
You may think as follow: "The back side has to be either red or white, that sounds fair, the probability is 50 %." But this is wrong.
As mentioned, we have three different cards. But the fact that one visible side is white does not mean that both possibilities do have the same probability. There are overall three white card sides: one has a red back side, and both others are the front and the back of the same card; i.e. white-red, white1-white2, and white2-white1. The conclusion is that the probability for a white back side is 2:3 or 66,67 %, and not 50:50. If you play enough games against the banker, he will bleed you dry for sure.
Two flies are sitting on a column, one at the bottom (x) and the other at the top (y). The distance between them is 126 cm. The column is decorated with a stripe which is winded 3.5 times around the column. The stripe has a bottom silver border and a top golden border. The column's circumference is 48 cm.
Suddenly, the bottom fly starts crawling from point x (the lowermost end of the golden border) along the golden border. At the same time, the other fly at y (the uppermost end of the silver border) crawls downwards along the silver border.
What distance have the flies covered when they are at the same height?
>>> 105 cm each
Each fly has crawled 105 cm.
This can be seen when the column surface is uncoiled. The short site is the circumference (48 cm), the long site is equivalent to the height (126 cm). The height gives place to 3.5 windings of the stripe, or 126 : 3.5 = 36 cm per winding.
The golden border is the hypotenuse of a right-angled triangle with the legs of 36 cm and 48 cm, respectively. Using Pythagoras' theorem, the length of the hypotenuse is 60 cm. Hence, the length of the golden (and also the silver) border is 60 cm × 3.5 = 210 cm. Half of this length is the distance that each fly has crawled, which then have the same distance from the ground (they arrive at the points x1 and y1).
Can you arrange the odd digits 1, 3, 5, 7, and 9, and the even digits, 2, 4, 6, and 8, in such a way that the odd ones add up to the same as the even ones
You can use arithmetical signs and decimals, but the idea is to try and arrive at the simplest possible solution. There are, of course, many possible answers.
What is the four-digit number (no zeros) in which the third digit is the number of "winds," the first digit is one-half of the third, the second digit is double the third and the last digit is one-half the sum of the first three
I am on three legs when I rest and one when I work.
What am I