Clean riddles

logicmathsimpleclean

Is half of two plus two equal to two or three?
Three. It seems that it could almost be either, but if you follow the mathematical orders of operation, division is performed before addition. So... half of two is one. Then add two, and the answer is three.
80.88 %
50 votes
cleanlogic

You are standing next to three switches. You know these switches belong to three bulbs in a room behind a closed door – the door is tight closed, and heavy which means that it's absolutely impossible to see if any bulb is on or not. All three switches are now in position off. You can do whatever you want with the switches and when you are finished you open the door and go into the room. While in there you have to tell which switch belongs to which bulb. How will you do that?
Turn on the first switch and wait for a while. Turn off the first one and turn on the second. Go into the room. One bulb is shining, the second bulb is hot and the third one nothing.
80.87 %
83 votes
logicmathsimpleclean

The digits 0-9(0,1,2,3,4,5,6,7,8,9) can be rearranged into 3628800 distinct 10 digits numbers. How many of these numbers are prime?
None. The sum of numbers from 0-9(0,1,2,3,4,5,6,7,8,9) is 45 and therefore can be divisible by 3 and 9.
80.86 %
43 votes
logiccleansimple

Shadow drove into the Speedy Service Station and pulled up to the pumps. "Fill it up, please," said Shadow. " This may sound strange," said the owner, "but I'd rather fill two cars from out of town than one car from this town." Shadow looked across the small town and replied, "I know just what you mean." Why would the owner feel this way?
The owner would rather fill two cars from anywhere than one car from town because he would make twice the amount of money.
80.86 %
43 votes
cleanlogicwhat am I

What word in the English language does the following: the first two letters signify a male, the first three letters signify a female, the first four letters signify a great man, the first six letters signify a drug, while the entire world signifies a great woman. What is the word?
Heroine
80.86 %
43 votes