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Some of you may have seen this optical illusion before. It appears to be a triangle made up of four parts, that when rearranged create an extra hole that shouldn’t be there. I’ve seen all sorts of ridiculous explanations (see the comments) on different websites, but it is in fact VERY simple. Look at the two triangles within the larger one. The smaller of the two triangles, the blue one, has a slope of .4, or 2/5. Now look at the red one. It has a slope of 3/8, which is .375, not the same slope as the other triangle. This means that off the bat, THIS IS NOT A TRIANGLE. It’s a quadrilateral. You can tell if you look closely that they are not in fact straight. This sort of makes the rest of the illusion moot, because it’s trying to convince you that it’s a triangle. They don’t specifically say that it is a triangle, but they call it figure ABC, when it really is figure ABCD. Since there are four points, and not three, it is possible to make a hole in the “triangle” by rearranging the parts to make it concave or convex. End of story.
2 This riddle has been around for a while, but it’s always amusing to me. See if you can figure out the answer.
Three people check into a hotel. They pay $30 to the manager and go to their room. The manager suddenly remembers that the room rate is $25 and gives $5 to the bellboy to return to the people. On the way to the room the bellboy reasons that $5 would be difficult to share among three people so he pockets $2 and gives $1 to each person. Now each person paid $10 and got back $1. So they paid $9 each, totalling $27. The bellboy has $2, totalling $29. Where is the missing $1?
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SOLUTION: (no cheating now…)
The solution to this problem is that the numbers have been added incorrectly. The question misleads you by adding the bellboy’s two dollars to the $27 paid, when really those two dollars are part of the $27. In the end, the Manager has $25 for the room, and the bellboy has $2 of the $27 dollars the men now have paid.