Page 100 - (DK) How to be a GENIUS?

BRAIN GAMES

THE MAGIC OF

MATH

A lot of math involves figuring out
patterns and relationships between
Domino divining
g
different numbers. Try out these D m n i i i g
o
s
s
a
U
o
r
o
b
i
clever mind-bending math tricks on Use basic subtraction skills to discover the
d
i
e
d
t total on a domino hidden in your friend’s hand.
h
e
n
o
m
o
your friends and family and find out
how math can be much more fun S e 1
Step 1
Step
Give your friend a set of dominoes and ask him or her to
than you think. G y r e e m a a h h
w
c choose one without letting you know what it is.
h
w
o
t
o
y
k
e
Step 2
S
Step 2
Ask him or her to pick one of the numbers on the domino
A h h p c o e u e o h o n
k
e
p
t
’
s
s
and to do the following problems with it—it’s okay to use
a
o
l
l
a a calculator:
a
l
O
ǩ ǩ ǩ 0XOWLSO\ E\
0XOWLSO

\
X
E\
\
T e a s e
G
s “ ǩ ǩ $GG
The answer is “9” ”
X
\
ǩ ǩ 0XOWLSO\ E\
O
T s a e sy r k
w h s r
This is an easy trick to start off f
e
WK
WK
E
K
G
P
H
$GG
Q
u e u r ǩ ǩ $GG WKH RWKHU QXPEHU
d a e n m t
with, because you are letting math
n
shown on the domino
o
e
h w r s shown on the domino
w
o yo
k o
do all the work for you. Ask your
fr n to x ct f
Step 3
St
o h o t e e S e 3
friend to exactly follow the steps
r k n
w h a sw A h or her t o o t ell y ou
of the trick and the answ
h
him
Ask
Ask him or her to tell you thethe
of the trick and the answer r
l
w s e
e a a answer . If y ou then subtr r act
answer. If you then subtract
s
will always be the same: e
w
I
will always be the same: 9. 9 9.
u
t
o
,
S e 1 14 from this, you will be left
Step 1
Step 1
with a two-digit number,
B r o w w n m r,
i
orr
which
s
n
which will correspond to
o
a c of t t t k r t w will c o espond t o
p
n m
m
y
b
u
v
d
b a piece of paper, fold it, and hand it to your frie d d the very same numbers
Before you start the trick, write the number 9 on n
a
h
e h
o e d to ou r o on your friend’s domino. .
f
n
m
o
d
o o
a piece of paper, fold it, and hand it to your friend,
k
but tell him or her not to look at
but tell him or her not to look at it. it
S e
Step
Step 2 2
H d
u ri
d a
o o e l r d s
lo n m r
to do the following:
to do the following:
Hand your friend a calculator and ask him or her
Hand your friend a calculator and ask him or her r
ǩ S Q
ǩ 7\SH LQ KLV RU KHU DJH
ǩ G H K D
ǩ G H P H I L R
ǩ $GG WKH QXPEHU RI WKHLU KRXVH H
ǩ G H V X L V WK U
P H
I
ǩ $GG WKH ODVW IRXU GLJLWV RI WKHLU SKRQH QXPEHU
ǩ $GG WKH QXPEHU RI SHWV WKH\ KDYH R Q P
V
ǩ $GG WKH ODVW IRXU GLJLWV RI WKHLU SKRQH QXPEHU
H
G
D
H
ǩ $GG WKH QXPEHU RI SHWV WKH\ KDYH
ǩ XO P H I W
O\ \ UV Q LV UV UV
ǩ 0XOWLSO\ E\
ǩ 0XOWLSO\ E\
ǩ G H HUV WKH\ KDYH
H KD
ǩ $GG WKH QXPEHU RI EURWKHUV DQG VLVWHUV WKH\ KDYH
J
a ǩ $GG WKH GLJLWV RI WKH DQVZHU WRJHWK K KHU ,I WKH H
R KH Q
w
s
H RJ K
o
$GG WKH GLJLWV RI WKH DQVZHU WRJHWK KHU ,I WKH
o dd ho t n e gi s h ,
t o e
answer is more than one digit, ask h him or her
h m h a
g e ogether, and to keep adding
to add those digits together, and to k
d
t
re
o o
them together until there is only y
them together until there is only d d i
il there is only digit left
S e n ntil there is only digit left. f
Step 3
S w u
w t a d e c of
Show your friend the piece of pap p
Show your frie iend the piece of paper
with the answer w w tt
o
with the answ w wer written on it. it t
wer written on
98
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