Simple Logic/Math Question

[Petra]

What is the answer to this question, and why is it the answer:

John likes 400 but not 300; he likes 100 but not 99; he likes 3600 but not 3700. Which does he like?

a) 900

b) 1000

c) 1100

d) 1200


I just can't work it out. :dunce:

[slimshady2357]

What is the answer to this question, and why is it the answer:

John likes 400 but not 300; he likes 100 but not 99; he likes 3600 but not 3700. Which does he like?

a) 900

b) 1000

c) 1100

d) 1200


I just can't work it out. :dunce:

400, 100 and 3600 are all squares, 20, 10, 60 respectively. Therefore he likes a) 900, the only square (30).

[Petra]

Brilliant!

Thank you, and thank you for making your answer hidden with spoilers - very cool. :cool:


I did one of those silly Tickle IQ tests while kicking back and surfing teh intaweb after work, and that was the only question that I answered with pure guesswork. Everything else I was pretty certain of, but that one totally had me. Thanks. :)

[seebs]

Yay! I got it too.

But thanks to the existing spoiler, this post contributes NOTHING AT ALL but gloating.

[Ensign Steve]

1000 isn't square?!

/me bogs.

[John Carter]

1000 isn't square?!

* Ensign Steve bogs.

Nope. sqrt (1000) = 10 * sqrt (10). It is a cube, though.

[Skep]

It is the square of 103/2. It's just not a perfect square (the square of an integer.) :)

[John Carter]

It is the square of 103/2. It's just not a perfect square (the square of an integer.) :)

Heh. Why is it that I knew exactly what you had posted before I clicked on the spoiler button?

Your claim depends on the particular set we are dealing with. If we are talking R, then yes, you are correct and every number is the square of 2 other reals. But if we are restricted to Z, then 103/2 is meaningless.

[Skep]

It is the square of 103/2. It's just not a perfect square (the square of an integer.) :)

Heh. Why is it that I knew exactly what you had posted before I clicked on the spoiler button?
You must be psychical. :)

Your claim depends on the particular set we are dealing with. If we are talking R, then yes, you are correct and every number is the square of 2 other reals. But if we are restricted to Z, then 103/2 is meaningless.
You didn't use the doublestruck letters http://img187.echo.cx/img187/7461/r1vl.gif and http://img187.exs.cx/img187/5185/z9kt.gif to represent the reals and integers, respectively. :tease:

[John Carter]

Ooops, I made a mistake in my last post.

If we are talking about the reals then every positive number is a square.

[JoeP]

except for this:
http://img187.echo.cx/img187/7461/r1vl.gif and http://img187.exs.cx/img187/5185/z9kt.gif
'cos it don't like bbcode inside the spoiler text= value