Puzzle 1
You have a very large number of generic plastic building blocks, each in the shape of a cube.
Think about how many cubes you would need in order to construct a giant cube with 16 small cubes along each edge.
If you were to then remove the outside layer, how many small cubes would you have removed?
Puzzle Copyright © Kevin Stone
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Hint
How large would the smaller cube be?
Answer
1,352 small cubes.
Reasoning
The original large cube with 16 small cubes along each edge would require 16 x 16 x 16 = 4,096 small cubes.
Removing the outside layer would leave a large cube now with 14 small cubes along each edge (which requires 14 x 14 x 14 = 2,744 small cubes).
It isn't 15 small cubes because you're removing both ends of an edge.
Therefore, you have removed 4,096 − 2,744 = 1,352 small cubes.
Puzzle 2
These words have had their vowels removed, can you replace them to find some girl's names:
gl
rs
dth
ptsy
mxn
dwn
gth
dry
Puzzle Copyright © Kevin Stone
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Hint
The first letters of the names are: G, R, E, P, M, E, A, A.
Answer
gl = Gail
rs = Rose or Iris
dth = Edith
ptsy = Patsy
mxn = Maxine
dwn = Edwina or Dawn
gth = Agatha
dry = Audrey
Puzzle 3
Unluckily, last week I lost my measuring tape. It was unlucky as I had to measure Billy's toy box.
Luckily though I could remember that the top had an area of 720 square inches, the side was 800 square inches, and the end was 360 square inches.
What were the true dimensions of the toy box?
Puzzle Copyright © Kevin Stone
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Hint
A little algebra might help.
Answer
Width=40, height=20, depth=18.
Reasoning
If we call the height H, the width W and the depth D we have:
H x W = 800
H = 800 ÷ W (1)
W x D = 720
W = 720 ÷ D (2)
H x D = 360
H = 360 ÷ D (3)
Using (1) and (3) we have:
800 360
——— = ———
W D
800 x D = 360 x W
Using (2):
800 x D = 360 x 720
———
D
800 x D2 = 259,200
D2 = 324
D = 18
Using (2), W = 40.
Using (1), H = 20.
Puzzle 4
Which two letters come next in this sequence:
ME · VE · EA · MA · JU · SA · UR · ?
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Answer
NE.
From Neptune. The first two letters from the planets in sequence: MErcury, VEnus, EArth, MArs, JUpiter, SAturn, URanus, NEptune.