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: 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: 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: Not far off shore a ship stands with a rope ladder hanging over her side. The rope has 10 rungs. The distance between each rung is 12 inches. The lowest rung touches the water. The ocean is calm. Because of the incoming tide, the surface of the water rises 4 inches per hour. How soon will the water cover the third rung from the top rung of the rope ladder?
Answer: When a problem deals with a physical phenonmenon, the phenonmenon should be considered as well as the numbers given. As the water rises, so does the rope ladder. The water will never cover the rung.