Ted was lost while driving around the country and saw a house. He parked under a nearby tree and started toward the house. As soon as he got out of his car a huge dog lunged at him from the opposite side of the tree. Fortunately the dog was chained and Ted managed to stay out of reach. Finding no one home at the house, Ted returned to his car, but as he approached the dog lunged at him again. The chain was so long the snarling animal could reach both car doors. How did Ted escape the dog and get back into his car?
Ted moved slowly around the tree keeping just out of the dog’s reach. The animal followed, winding its chain around the tree until it was too short to reach Ted’s car
Two women apply for a job. They are identical and have the same mother, father and birthday. The interviewer asks, “Are you twins?” to which they honestly reply, “No”.
Priscilla gave her brother Bruce as much money as Bruce started with. Bruce gave Priscilla as much money as Priscilla had left. Priscilla then gave Bruce as much as Bruce had left, which left Priscilla broke. Bruce had $80.00.
How much money did Priscilla and Bruce start with?
A princess is as old as the prince will be when the princess is twice the age that the prince was when the princess’s age was half the sum of their present ages.
This one took a while to figure out and there are numerous valid ways of finding the answer.
Here is the solution I came up with
I created the following table from the riddle:
Current
Future
Past
Princess
x
2z
(x+y)/2
Prince
y
x
z
I then created three equations, since the difference in their age will always be the same. d = the difference in ages x – y = d 2z – x = d x/2 + y/2 – z = d
I then created a matrix and solved it using row reduction.
x
y
z
1
-1
0
d
-1
0
2
d
.5
.5
-1
d
It reduced to:
x
y
z
1
0
0
4d
0
1
0
3d
0
0
1
5d/2
This means that you can pick any difference you want (an even one presumably because you want integer ages). Princess age: 4d Prince age: 3d
Ages that work
Princess
Prince
4
3
8
6
16
12
24
18
32
24
40
30
48
36
56
42
64
48
72
54
80
60
To see other solutions check out the comments from when I posted this on my blog.
I can kill people, or cause great pain. You eat me. I can mean you’re crazy. I hold things together. I help climbers stay safe. I can replace a swear. And I’m on a violin.
People with nut allergies can die from eating nuts. Being hit in the nuts hurts (I speak from experience. Painful, painful experience). You eat nuts (unless you’re allergic, in which case you should run away). If someone says you’re nuts, it doesn’t mean you’re a peanut or an almond. Nuts and bolts hold things together. A climber’s nut or chock wedges into a rock. Instead of swearing, you can say, “Aww nuts!”. And finally, the nut on a violin is a small piece of hard material that supports the strings.