Best riddles

cleanwhat am Isimplelogic

I am pronounced as a one letter alphabet. I am written with three letters. I am complete with just two letters. I am double. I am blue I am black I am brown I am gray I am yellow and I am green. I can read from both ends. I appear the same every way! What am I?
Eye.
82.72 %
48 votes
logicmath

A women walks into a bank to cash out her check. By mistake the bank teller gives her dollar amount in change, and her cent amount in dollars. On the way home she spends 5 cents, and then suddenly she notices that she has twice the amount of her check. How much was her check amount?
The check was for dollars 31.63. The bank teller gave her dollars 63.31 She spent .05, and then she had dollars 63.26, which is twice the check. Let x be the dolars of the check, and y be the cent. The check was for 100x + y cent He was given 100y + x cent Also 100y + x - 5 = 2(100x + y) Expanding this out and rearranging, we find: 98y = 199x + 5 Which doesn't look like enough information to solve the problem except that x and y must be whole numbers, so: 199x ≡ -5 (mod 98) 98*2*x + 3x ≡ -5 (mod 98) 3x ≡ -5 ≡ 93 (mod 98) This quickly leads to x = 31 and then y = 63 Alternative solution by substitution: 98y = 199x + 5 y = (199x + 5)/98 = 2x + (3x + 5)/98 Since x and y are whole numbers, so must be (3x + 5)/98. Call it z = (3x+5)/98 so 98z = 3x + 5, or 3x = 98z - 5 or x = (98z - 5)/3 or x = 32z-1 + (2z-2)/3. Since everything is a whole number, so must be (2z-2)/3. Call it w = (2z-2)/3, so 3w = 2z-2 so z = (3w+2)/2 or z = w + 1 + w/2. So w/2 must be whole, or w must be even. So try w = 2. Then z = 4. Then x = 129. Then y = 262. if you decrease y by 199 and x by 98, the answer is the same: y = 63 and x = 31.
82.72 %
48 votes
stupidtricky

Mike was watching TV and all of a sudden he leaps to his feet and says, "That's Simon", pointing at someone who was at the screen. Then his brother Mark comes in, looks at his brother, then looks back at the TV and says, "So it is." How do they know Simon if they hadn't seen him before, no pictures, nothing?
He is their lost, separated triplet brother.
82.69 %
40 votes
mathcleansimplelogicstory

Farmer Brown came to town with some watermelons. He sold half of them plus half a melon and found that he had one whole melon left. How many melons did he take to town?
Easy, three melons.
82.69 %
40 votes