Presidents and Parents

How could the 22nd and the 24th U.S. Presidents have the same parents, but not be brothers?

The 22nd and 24th U.S. presidents were both the same person – Grover Cleveland.

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

XQQQME

What is this phrase? XQQQME

Excuse me. Literally, x + q’s + me.

Posted in Brain Teasers
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A Silent Murder Witness

Emily witnessed a murder in early January but didn’t call the police. Why?

It was a murder of crows.

Posted in Brain Teasers

What House Weighs The Least?

What type of house weighs the least?

A lighthouse.

Posted in Riddles

Banana Dresser Grammar

What do these words have in common?

1. Banana
2. Dresser
3. Grammar
4. Potato
5. Revive
6. Uneven
7. Assess

If you move the first letter to the end of the word, it forms the same word backwards. Banana = ananab, dresser = resserd, and so on.

Posted in Brain Teasers

The Ants Go Marching

Three ants are walking in the same direction. The first ant has two ants behind him, the second ant has one in front and one behind, but the third ant has one in front and one behind too. How is this possible?

The ants are in a circle. Lets say the ants are A, B and C. A has has B and C behind him, B has A in front and C behind, and C has B in front and A behind.

Posted in Brain Teasers

The Longest Pregnancy

A baby was born four years after its parents died in a car crash. How was this possible?

Amazingly, this actually happened. The parents died in a crash crash and their parents fought for the rights to the four frozen embryos left by their late children. After a surrogate pregnancy, the baby was born with DNA matching their deceased parents.

Posted in Brain Teasers

If This Site Had a Phone Number

If this site had a phone number, I would want it to be 743-3537. Why?

Because the numbers on a phone would spell the word RIDDLES.

Posted in Brain Teasers

Hilda’s Age

When Randolph asked Hilda how old she was, Hilda replied that in two years she would be twice as old as she was five years ago. How old is Hilda?

Aside from the potential response that it’s rude to ask the age of a lady, the answer can be worked out mathematically.

x + 2 = 2(x – 5)
x + 2 = 2x – 10
x + 12 = 2x
12 = x
In two years she’ll be 14, which is twice her age 5 years ago (7).

Posted in Brain Teasers