Seasons, Seconds, Centuries and Minutes

What is in seasons, seconds, centuries and minutes but not in decades, years or days?

The letter “n”.

Posted in Riddles

Plum Taking

A man without eyes saw plums on a tree.
He neither took them nor left them, how can this be?

The man had only one eye and took one plum. (note singular versus plural)

Posted in Brain Teasers

What is the First Number of the Sequence?

If a number in a numeric sequence is 17 and the second number is 3, what is the first number?

I hesitated to add this because it’s poorly worded, ambiguous and the answer could be almost anything. I prefer teasers with a single answer, but there you go.

If you came up with a different answer and can explain how you did it, don’t think you’re wrong. It’s probably just as valid. Feel free to share yours in the comments.

My answer for the first number is 2.

Here’s how I got it.

The generic rule for a number in the sequence is: 2^(n – 1) + 1, where n is the position in the sequence.

Note: The teaser doesn’t specify the position of 17. In this case, it’s fifth.

Position 1: (so n = 1) is 2^(1 – 1) + 1 = 2

Position 2: 2^(2 – 1) + 1 = 3

Position 3: 2^(3 – 1) + 1 = 5

Position 4: 2^(4 – 1) + 1 = 9

Position 5: 2^(5 – 1) + 1 = 17

For the curious, the next 5 numbers of the sequence would be:

Position 6: 2^(6 – 1) + 1 = 33

Position 7: 2^(7 – 1) + 1 = 65

Position 8: 2^(8 – 1) + 1 = 129

Position 9: 2^(9 – 1) + 1 = 257

Position 10: 2^(10 – 1) + 1 = 513

Posted in Brain Teasers

Many and One

We are many and one,
We wave and we drum,
We will cover a stare,
With you everywhere.

What are we?

Hands.

Posted in Riddles
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A Corny Question

A merchant has 21 sacks of grain: 7 full, 7 half-full and 7 empty. He wants to divide them equally among his three sons. How can he do this, without transferring any grain between sacks, so each son has the same quantity of grain and number of sacks?

We know each son must end up with 7 sacks and 3.5 sacks of grain, since (7 sacks + 7 half sacks) / 3 = 3.5 sacks each.
There are two solutions.

Solution 1
Son 1: 3 full, 1 half-full and 3 empty.
Son 2: 3 full, 1 half-full and 3 empty.
Son 3: 1 full, 5 half-full and 1 empty.

Solution 2
Son 1: 2 full, 3 half-full and 2 empty.
Son 2: 2 full, 3 half-full and 2 empty.
Son 3: 3 full, 1 half-full and 3 empty.

Posted in Brain Teasers

A Big Rig Crossing a Bridge

An 18-wheeler is crossing a 4 kilometer bridge that can only support 10,000 kilograms and that’s exactly how much the rig weighs. Halfway across the bridge a 30 gram sparrow lands on the cab, but the bridge doesn’t collapse. Why not?

Since the bridge is 4 kilometers long, the halfway point would be 2 kilometers. The 18-wheeler would have used much more than 30g of fuel to drive 2 kilometers.

Posted in Brain Teasers

Fill in the Missing Element

Here is a series of numbers:

16 06 68 88 ___ 98

What belongs in the blank spot?

87 is the common answer to this, but it has to be flipped upside down, so I consider L8 more correct.

If you flip the numbers horizontally by 180 degrees:

86 87 88 89 90 91

You see that the blank spot is 87, counting from 86 to 91. However, you need to flip it around, so it becomes L8.

Posted in Brain Teasers

Brothers And Sisters Of Leopold

If Leopold had one more sister he would have twice as many sisters as brothers.
If he had one more brother he would have the same number of each.

How many brothers and sisters does Leopold have?

Three sisters and two brothers.

Posted in Brain Teasers

Show Your Work

Solve this one carefully!

230 – 220 x 0.5 = ?

You probably won’t believe it, but the answer is 5! How can this be true?

The answer is 120, and 5! = 5 × 4 × 3 × 2 × 1 = 120

Credit to John May for this one.

Posted in Brain Teasers

Find the Three Mammals

The largest crowd at the flea market came looking for bargains.
I took off the peel and ate the banana.
He has no judgement, no sense altogether.

Find the three mammals in these statements.

1. Camel (CAME Looking)
2. Eland (peEL AND)
3. Seal (senSE ALtogether)

Posted in Brain Teasers