Riddle: How many pluses should we put between the digits of 987,654,321 to get a total of 99, and where?
Answer: (6) 9 + 8 + 7 + 6 + 5 + 43 + 21= 99 (7) 9 + 8 + 7 + 65 + 4 + 3 + 2 + 1= 99
Riddle: Twelve flags stand equidistant along the track at the stadium. The runners start at the first flag. A runner reaches the eighth flag 8 seconds after he starts. If he runs at an even speed, how many seconds does he need altogether to reach the twelfth flag?
Answer: Not 12 seconds. There are 7 segments from the first flag tot the eighth, and 11 from the first to the twelfth. He runs each segment in 8/7 seconds; therefore, 11 segments take 88/7= 12 4/7 seconds.
Riddle: A woman went into a bank to cash an insurance refund check. By mistake the teller gave her dollars for cents and cents for dollars. She put the money in her purse but accidentally dropped a nickel on the floor. When she got home, she found that she had exactly twice the amount of the check she had cashed. She didn't have any money in her wallet before going to the bank. What was the exact amount of that check?
Answer: The amount must have been \$31.63. She received \$63.31. After she dropped a nickel there would remain the sum of \$63.26, which is twice the amount of the check.
Riddle: My only timepiece is a wall clock. One day I forgot to wind it and it stopped. I went to visit a friend whos watch is always correct, stayed awhile, and then went home. There I made a simple calculation and set the clock right. How did I do this even though I had no watch on me to tell how long it took me to return from my friend's house?
Answer: Before I left, I wound the wall clock. When I returned, the change in time equaled how long it took to go to my friends house and return, plus the time I spent there. But I knew the latter because I looked at my friends watch when I arrived and left. Subtracting the time of the visit from the time I was absent from my house, and dividing by 2, I obtained the time it took me to return home. I added this time to what my friend watch showed when I left, and set the sum on my wall clock.
Riddle: Given two 2s, "plus" can be changed to "times" without changing the results: 2 + 2= 2 x 2. The solution with three numbers is easy too: 1 + 2 + 3= 1 x 2 x 3. What is the answer for 4 numbers and for 5 numbers?
Answer: Solution for 4 numbers: 1 + 1 + 2 + 4= 1 x 1 x 2 x 4. Solution for 5 numbers: 1 + 1 + 1 + 2 + 5= 1 x 1 x 1 x 2 x 4  1 + 1 + 1 + 3 + 3= 1 x 1 x 1 x 2 x 4 1 + 1 +2 + 2 + 2= 1 x 1 x 2 x 2 x 2
Riddle: A girl is twice as old as her brother and half as old as her father. In 50 years, her brother will be half as old as his father. How old is the daughter now?