Math Is Fun Forum

Jai Ganesh

Administrator

Registered: 2005-06-28

Posts: 48,422

Math Riddles

Q: Why should you never mention the number 288 in front of anyone?
A: Because it is too gross (2 x 144 - two gross).
* * *
Q: How is the moon like a dollar?
A: They both have 4 quarters.
* * *
Q: How can you add eight 8's to get the number 1,000? (only using addition)
A: 888 +88 +8 +8 +8 = 1,000 .
* * *
Q: What is the smallest three digit palindrome divisible by 18? Can you solve this without a brute force examination of possibilities?
A: 252.
* * *
Q: How many eggs can you put in an empty basket?
A: Only one, after that the basket is not empty.
* * *
Q: Where can you buy a ruler that is 3 feet long?
A: At a yard sale.
* * *
Q: When things go wrong, what can you always count on?
A: Your fingers.
* * *
Q: What coin doubles in value when half is deducted?
A: A half dollar.
* * *
Q: What has 3 feet but no toes?
A: A yard stick.
* * *
Q: Why are diapers like 100 dollar bills?
A: They need to be changed.
* * *
Q: What goes up and never comes down?
A: Your Age.
* * *
Q: Why is the longest human nose on record only 11 inches long?
A: Otherwise it would be a foot.
* * *
Q: Why didn't the quarter roll down the hill with the nickel?
A: Because it had more cents.
* * *

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It appears to me that if one wants to make progress in mathematics, one should study the masters and not the pupils. - Niels Henrik Abel.

Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.

Monox D. I-Fly

Member

From: Indonesia

Registered: 2015-12-02

Posts: 2,000

Re: Math Riddles

Q: What is the smallest three digit palindrome divisible by 18? Can you solve this without a brute force examination of possibilities?
A: 252.

How did you find that without brute force?

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Actually I never watch Star Wars and not interested in it anyway, but I choose a Yoda card as my avatar in honor of our great friend bobbym who has passed away.
May his adventurous soul rest in peace at heaven.

Jai Ganesh

Administrator

Registered: 2005-06-28

Posts: 48,422

Re: Math Riddles

Hi Monox D. I-Fly,

Given : The smallest 3 digit number divisible by 18. Therefore, the required number must be an even number; the first 3 digit palindrome number is necessarily even.
Since it is a 3-digit even number and it is a palindrome number, which is divisible by 9, this this the first such number, viz. 252.

Given the conditions, we arrive at 252.

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It appears to me that if one wants to make progress in mathematics, one should study the masters and not the pupils. - Niels Henrik Abel.

Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.

Monox D. I-Fly

Member

From: Indonesia

Registered: 2015-12-02

Posts: 2,000

Re: Math Riddles

Ah, right...

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Actually I never watch Star Wars and not interested in it anyway, but I choose a Yoda card as my avatar in honor of our great friend bobbym who has passed away.
May his adventurous soul rest in peace at heaven.