Puzzle 1
How many cubic feet of earth are removed …
… to make a hole 4 feet wide by 7 feet long by 2 feet deep?
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Hint
Read the question carefully.
Answer
56 cubic feet (= 4 x 7 x 2).
We usually ask how much earth there is in a hole, which of course there is none!
Puzzle 2
Can you find every occurrence of the word MAY that appears in this grid (horizontally, vertically, or diagonally)?
The hint will reveal the number of times it occurs, but where are they?
Note: this puzzle is not interactive, and the letters cannot be selected.
Puzzle Copyright © Kevin Stone
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Hint
The word MAY appears 39 times.
Answer
The word MAY appears 39 times.
Puzzle 3
Which number, when written as a word, makes this true:
Cleverly, there are exactly ? E's in this sentence.
Puzzle Copyright © Kevin Stone
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Hint
Does ONE work, does TWO work? How many E's are there already?
Answer
Twelve.
"Cleverly, there are exactly twelve E's in this sentence."
Puzzle 4
If one small rabbit can dig a warren in nine hours, a medium rabbit can dig a warren in 6 hours, and a large rabbit can dig a warren in four and a half hours.
How long will it take one small, one medium, and one large rabbit, to dig a warren if they all work together?
Puzzle Copyright © Kevin Stone
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Hint
How much of a warren can each rabbit dig in one hour?
Answer
2 hours.
Reasoning
The small rabbit can dig a warren in nine hours, so digs 1 /9 in one hour.
The medium rabbit can dig a warren in 6 hours, so digs 1 /6 in one hour.
The large rabbit can dig a warren in four and a half hours, so digs 1 /4.5 in one hour.
1 Hour = 1 /9 + 1 /6 + 1 /4.5
To make the denominators all the same, we can multiply through by 18 /18 to give:
1 Hour = 2 /18 + 3 /18 + 4 /18
1 Hour = 9 /18
1 Hour = 1 /2
So in one hour, they have dug half a warren, the whole warren will therefore take 2 hours.
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