Puzzle 237
At the equator the radius of the earth is 6,378 km, so its circumference is almost exactly 40,000 km.
Imagine we had a long rope which went around the equator, this would of course be 40,000 km long.
If we now placed 1 metre sticks vertically all the way around and lay the rope on top of these sticks (so the rope would be 1m higher all the way around) how much extra rope would we require?
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Hint
Circumference = 2 x Radius x π .
Answer
6.28 metres, a lot less than you might think!
If we call the radius of the Earth R, then the difference between the two circumferences is:
2 x π x (R + 1) − 2 x π x R
= 2 x π metres
= 6.28 metres.
Puzzle 238
A grocer has to place 28,121 carrots into bags, each bag containing the same number of carrots, and using as few bags as possible.
If you think that one big bag will suffice, then feel free to calculate its size!
If we assume that more than one bag is used, how many are required?
Puzzle Copyright © Kevin Stone
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Hint
28,121 isn't a prime number.
Answer
61 bags.
Reasoning
Each bag contains 461 carrots.
How do we find the correct answer? An easy way is to keep dividing 28,121 by the prime numbers in sequence until one works.
2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31, 37, 41, 43, 47, 53, 59, 61.
Puzzle 239
How should these words actually be spelled, without using a dictionary.
bizz-ness
com-it-ee
sin-seer-lee
ark-ee-ollow-jist
Puzzle Copyright © Kevin Stone
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Hint
Be careful with the middle of the last word.
Answer
Business.
Committee.
Sincerely.
Archaeologist.
Puzzle 240
Can you find a word which can go in front of each of these words to make a new word?
colour
cress
fall
proof
shed
way
Puzzle Copyright © Kevin Stone
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Hint
The word begins with the letter W.
Answer
Water.
Watercolour, watercress, waterfall, waterproof, watershed, waterway.
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