Puzzle 57
Take a normal piece of paper, exactly 0.1 mm thick.
Fold it in half, and then in half again, and again, and again.
Do this a total of 50 times.
How thick would the final paper be (if this could be done)?
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Hint
We'll assume that we can actually fold it this many times.
Answer
Very thick indeed! The paper doubles in thickness with each fold. If we could fold it 50 times, it would be around 70 million miles thick!
1 fold would be 0.1 + 0.1 = 0.1 x 2 ^ 1 = 0.2 mm
2 folds would be 0.1 + 0.1 + 0.1 + 0.1 = 0.1 x 2 ^ 2 = 0.4 mm
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10 folds would be 0.1 x 2 ^ 10 = 102.4 mm
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50 folds would be 0.1 x 2 ^ 50 = 112,589,990,684,262.4 mm = 112,589,990.7 km (around 70 million miles).
Puzzle 58
Combine the word fragments below to produce pairs of words that have opposite meanings. There are 9 pairs of words, one pair on each line.
For example, USE REF EPT ACC becomes ACCEPT + REFUSE.
AB ANT RCE SCA UND
WA RY RD BR ICE CO AVE
ETY NG SAF ER DA
ACT AND CO EXP NTR
WN US UNK NO MO FA
TR TE IBU HER GAT DIS
CAL HO RI RTI TAL VE ZON
TIO AL CID EN ENT INT NAL AC
OWL OR KN IGN GE ED CE AN
Puzzle Copyright © Elliott Line This puzzle appeared in Mensa's EnigmaSig (194.21) and is used with permission.
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Hint
The first letters of one half of the words are: A, B, D, C, F, D, H, A, I.
Answer
ABUNDANT + SCARCE
BRAVERY + COWARDICE
DANGER + SAFETY
CONTRACT + EXPAND
FAMOUS + UNKNOWN
DISTRIBUTE + GATHER
HORIZONTAL + VERTICAL
ACCIDENTAL + INTENTIONAL
IGNORANCE + KNOWLEDGE
Puzzle 59
These five words are connected somehow, which word is missing?
origami
reptilian
?
nuclei
gliding
echo
Choose from:
albatross, approved, bingo, furtive, pedalled, zebra
Puzzle Copyright © Kevin Stone
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Hint
The words are linked by their letters.
Answer
Approved.
The initial letters spell ORANGE and the last letters spell INDIGO.
Puzzle 60
At a recent visit to the reptile house at the local animal sanctuary, I counted a total of 27 heads and 70 feet.
I was counting snakes, lizards, and people and I know that there were exactly twice as many lizards as people.
How many snakes did I count?
Puzzle Copyright © Kevin Stone
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Hint
Snakes don't have legs.
Answer
6 snakes, along with 7 people and 14 lizards.
Reasoning
We know that for each person (2 legs) there were 2 lizards (4 legs each).
Which means for every person, we can count a total of 10 legs.
Snakes don't have legs, so the total of 70 legs must have been 7 people (and 14 lizards).
This is a total of 21 heads, so the remaining 6 heads were all snakes.
Double-Checking
7 people gives 7 heads and 14 feet.
14 lizards gives 14 heads and 56 feet.
6 snakes gives 6 heads and 0 feet.
For a total of 6 + 7 + 14 = 27 heads, and 0 + 14 + 56 = 70 feet.
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