#2121 - Hard Maths Riddle

Using the digits 1 up to 9, two numbers must be made. The product of these two numbers should be as large as possible. All digits must be used exactly once. Which are the requested two numbers. ?

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The digits of the requested two numbers obviously form descending sequences. Furthermore, if you have two pairs of numbers with equal sums, the pair of which the numbers have the smallest absolute difference, is the one of which the numbers have the largest product. Using this knowledge, the two numbers can easily be constructed by placing the digits one by one, starting with 9 and ending with 1:
9

8 -> 96

87 -> 964

875 -> 9642

8753 -> 9642

87531
Conclusion: the requested two numbers are 9642 and 87531 (and the product of these two numbers is 843973902).

#2122 - TinTin Logic Riddle

TinTin is on an island and there are three crates of fruit that have washed up in front of him. One crate contains only apples. One crate contains only oranges. The other crate contains both apples and oranges.

Each crate is labeled. One reads 'apples', one reads 'oranges', and one reads 'apples and oranges'. He know that NONE of the crates have been labeled correctly - they are all wrong.

If he can only take out and look at just one of the pieces of fruit from just one of the crates, how can he label ALL of the crates correctly?

View Answer Discuss

Take a piece of fruit from the "apples and oranges" crate. If it's an apple then you know that is the "apples" crate since ALL THE CRATES ARE LABLED INCORRECTLY. This means the crate marked "apples" must be "oranges" and the crate marked "oranges" must be "apples and oranges".

#2123 - Pattern Puzzle

What do the following words have in common?

Assess
Banana
Dresser
Grammar
Potato
Revive
Uneven
Voodoo

View Answer Discuss

If you take the first letter , rest become palindrome

#2124 - Nonsense Riddle

Four men were in a boat on the lake. The boat turns over, and all four men sink to the bottom of the lake, yet not a single man got wet! Why?

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Because they were all married and not single.

#2125 - One Correct Answer

Here are three answers:
1. Answer A
2. Answer A or B
3. Answer B or C

There is only one correct statement.Identify It ?

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Because they were all married and not single.

#2126 - December Riddle

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

View Answer Discuss

The letter 'n'.

#2127 - December Maths Puzzle

I am thinking of a 6-digit number. The sum of the digits is 43.

And only two of the following three statements about the number are true:

(1) it's a square number,
(2) it's a cube number, and
(3) the number is under 500000.

December Maths Puzzle
View Answer Discuss

Only Statements 1 and 3 are true. the number is 499849.

7072 = 499849
499849<500000

#2128 - What Word Riddle

Pronounced as one letter,
And written with three,
Two letters there are,
And two only in me.
I am double, I am single,
I am black blue and gray,
I am read from both ends,
And the same either way.

What Word Riddle
View Answer Discuss

Eye

#2129 - Simple Maths Puzzle

In a certain country ½ of 5 = 3. If the same proportion holds, what is the value of 1/3 of 10 ?

Simple Maths Puzzle
View Answer Discuss

4
5/2 = 3 and 10/3 = x
(10/3)/(5/2) = 20/15 = 4/3
So x/3 = 4/3
x=4

#2130 - Science Series Puzzle

H, Be, F, S, Mn, Kr, In, Gd, Tl, ?

What's the next in the series?

Science Series Puzzle
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Fm.

These are the chemical elements whose atomic numbers are perfect squares.

1, 4, 9, 16, 25, 36, 49, 64, 81, 100.