Snail Up The Wall

A snail creeps 10 feet up a wall during the daytime, then falls asleep. It wakes up the next morning and discovers it slipped down 6 feet. If this happens each day, how many days will it take to reach the top of a 20 foot wall?

Four days.

Day 1: up to 10, down to 4
Day 2: up to 14, down to 8
Day 3: up to 18, down to 12
Day 4: up to 22 (20 really) and done

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Two Scruffy Dogs

Two scruffy dogs were walking down the street. The first dog turned to the other and said, “Do you realize that if one of your fleas jumped onto me we would have the same number of fleas?” The second replied, “Yes, but if one of your fleas jumped onto me I would have five times as many fleas as you.” How many fleas are on each dog to begin with?

2 and 4

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Two Three Four Fifteen

What is the missing number?

2 3 4 15 12
3 4 5 28 20
4 5 6 45 30
5 6 7 66 42
6 7 8 ?? 56

91. To get the number in the fourth column, you add the numbers in column 1 and 2, then multiply by the number in column 2. f(n,m) = (n + m) * m
For example, f(2,3) = (2 + 3) * 3 = 15. Thus f(6,7) = (6 + 7) * 7 = 91

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Jack, George and Anne

Jack is looking at Anne, but Anne is looking at George. Jack is married, but George is not. Is a married person looking at an unmarried person?

A) Yes
B) No
C) Cannot be determined

A. If Anne is married, she’s looking at George, who is unmarried. If Anne is unmarried, Jack is looking at her.

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Represent The Alphabet

What word or expression does this represent?

ABCDEFGHIJKLMNOPQRSTVWXYZ

Missing you (U).

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A Circular Island

A circular island with a diameter of 30 feet has a 30 foot tree stands at the center. A man cuts the tree down with his chainsaw, making the cut a foot up from the ground. The tree comes crashing down and hits the water but doesn’t splash. Why not?

It’s winter and the water is frozen.

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250 Lbs Across the River

Two boys weighing 50 pounds each and their older brother weighing 100 pounds wish to cross a river. Their boat will only hold 100 pounds. How can they all cross the river in the boat?

Two 50lb boys cross, one comes back.
100lb boy crosses, other 50lb boy returns
Both 50lb boys cross.

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Six Nine Twenty-Seven

What is N?

6, 9, 27, 54, N, 2241

675.

The next number in the sequence is n squared minus m or f(n,m) = n2 – m
f(6,9) = 62 – 9 = 27
f(9,27) = 92 – 27 = 54
f(27,54) = 272 – 54 = 675
f(54,675) = 542 – 675 = 2241

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Turn Two Into Five

How do you turn 2 into 5?

Turn it upside down and look at it in a mirror.

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From Cold To Warm In Four Steps

How do you get from cold to warm in four steps, changing only one letter at a time to form a new word at each step?

cold
cord
word
worm
warm

An alternative is:
cold
cord
word
ward
warm

Yet another option, thanks to Beth:
cold
cord
card
ward
warm

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