Page 101 - (DK) How to be a GENIUS?

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All in a row 222222222222
A l i
This is not just a great trick, it’s also a
t a o
t c
e
s
t
T s
ood way of practicing your multiplication
good way of practicing your multiplication = . M a th g en i u s Ka rl G a u s s
t
i
u m t
i
o p c
rl
Math genius Karl Gauss
en
Ka
d w
th
g
skills. Once again, the number 9 is
skills Once again, the number 9 is % ÷ ( (1777–1855) once added the
n h n m e 9
O c a
–
ed
e
7
d
ed
o
)
a
c
n
e
8
d
1
5
d
5
7
7
1
th
th
l
s
helping with the magic. 7 8 9 × n u m b er rs fr ro m 1 to 1 0 0 i n s eco n ds s. .
helping with the magic. c
a
t
rs
to
ds
o
numbers from 1 to 100 in seconds.
ec
to
h p g i
fr
fr
co
ers
er
c
o
a
H
fir
fir
n
fir
u
t
rs
i
w
s
a
rs
t
th
e
y
a
th
a
s
f
d
e
d
d
th
th
Step 1 He saw that if you add the first and
S e
y
+
1
t
0
1
1
.
et
(
)
m
u
,
rs
g
0
1
n
rs
er
o
0
l
as
as
et
b
ers
er
last numbers (1 + 100), you get 101.
u
Hand your friend a calculator, a pen, and a 4 5 -
d
o
u
c
d
u r
d
H
th
e
-
as
as
ec
co
eco
to
n
ec
A
eco
c
s
s
d
d
n
-
t
c
th
co
l
a
to
d
ng
ng
n
d
i
to
d
piece of paper. Ask him or her to write down n 6 Adding the second and second-to-last
piece of paper. Ask him or her to write down
d
e o r
o
h
e A
e
p
p
(2
es
es
ves
ve
+
y
ls
er
numbers (2 + 99) also gives you 101,
(2
ers
rs
these eight digits: 12345679. 9
these eight digits: 12345 5 1 2 3 n a u n m b s er rs o n . So 9 a 9 l ) l a ls u o g i ee ed to o u 1 0 1 ,
2
s
d
g
e
h
do
do
o
to
to
d
So
y
eed
o
y
i
n
and so on. So all you need to do isis
d
Step 2 2 + 101 x 50, which is 5,050. .
1
0
Step
1
0
101 x 50, which is 5,050.
,
5
ch
,
is
is
5
h
i
0
wh
0
x
wh
5
S e
Ask him or her to choose one of the digits.
i
Ask him or her to choose one of the digits. AC C 0
e
f
e n
o h
h
h
A
Step 3
S e
Whichever one your friend chooses, you must
u
u
,
s
n c
n y
e
W c
quickly multiply it by 9 in your head. So, for example,
quickly multiply it by 9 in your head. So, for example, e
m
,
.
e
u
n
y
i
k m
q
if he or she picks 1, 1 x 9 = 9; if he or she picks 2,
if he or she picks 1, 1 x 9 = 9; if he or she picks 2, 2
c
e
r
h
9
1 9
s
p
s
2 x 9 = 18; if he or she picks 3, 3 x 9 = 27, and so on. .
f
o
7
n
3
h
i
o
8

2
Step pl
Step 4 4
S e
Now ask your friend to use the calculator to multiply y
o o
Now ask your friend to use the calculator to mu
u
c
t

u
i
k u
N
the eight-digit figure by the number you have just
v
u
u
r
m
t
g e
g
t
h e
worked out. If your friend picked 1 in Step 3, the e
rked out If your friend picked 1 in Step 3, the
e 3
n
d
c
r n
o
o
w k
answer will be 111,111,111; if he or she picked 2, 2
answer will be 111,111,111; if he or she picked 2,
k
e
e
1
1
b
w
a
w
the answer will be 222,222,222; if he or she picked
k

e
2
2 2
b
w
w
h a
3, the answer will be 333,333,333, and so on. n
n s
3 3
3
e
i
e
e n
3
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20
Super adder
S p r a d r
Perform this trick well and you will
P f m h t c w d o w
c v i c y r f i d th t u r th
convince your friends that you are the
d
h
h
t p
Step 3
y
act
es
In
e
t
s
as
f
s
n
the
t
a
f
world
onl
d
w
s
e
world’s fastest adder. In fact, the only e o
s
adder
f
n
o
s
c p
a
d
skill you need to master is how to
e
s
skill l y ou need t o mas t er is how t o When your friend accepts the challenge don’t
e
h c
m r o le e o
When your friend accepts the challenge, don’t
h
1
lt
y
multiply by 11.
m l l y by 11. add the numbers together. Instead, simply
multipl
y
te
e
v
, m
add the numbers together. Instead, simply
e u h u e
e m ot y — h w
multiply the seventh number by 11—this will
o
ll
r
Step 1 give you the sum total of all ten numbers much h
S
e
n
u
l
m e
ha y
h r en c m
ca u
r
H d o u r friend a pencil a piec c e of f paper a with a calculator o fi r o
d
p
p
Hand
Hand your friend a pencil, a piece of paper, andand
with a calculator. .
more quickly than your friend can figure it out
more quickly than your friend can figure it out
and
c
w
c
,
her
do
a calculator, and ask him or her to do the following: :
a a
or
ask
him
oll
k
f
the
owing:
m
al
h
o
t
or
d
culat
a
ta
e
ǩ G Q R X H E Z Q For instance, if the ten numbers your friend d
ǩ :ULWH GRZQ WZR QXPEHUV EHWZHHQ DQG
t
t
ot
n m
e
o n
one beneath the other. wrote down were 7, 12, 19, 31, 50, 81, 131,
o
b
rs o

e
fr
r
,
,
3
5
3
Z
ǩ ǩ
$GG
WZ
ǩ $GG WKH WZR QXPEHUV WRJHWKHU DQG ZULWH WKDW 212, 343, 555, all you have to do is multiply the e
R
G
WKH
X
H
QXPEHU
5
W
W
U
W
8
H
ZULW
RJHWKHU
G
DQG
H
U
WKDW
H
V
1
al o
wrote down were 7, 12, 19, 31, 50, 81, 131
a
w

third new number beneath the other two.
a
thir d new number benea t o r o e h m er 3 t o m t y
e
e
12, 343, 555, all you have to do is multiply the
m by 1
g
ta
ǩ G H F G Q V J sum total of all the numbers. Don’t forg rg
1
ǩ $GG WKH VHFRQG DQG WKLUG QXPEHUV WRJHWKHU
f
seventh number, 131, by 11 to get 1,441, the
1 he
m
r
n
D
w
l
o
h
f
b
and write a fourth new number below them. you can use a pen and paper for this trick.
b
n
e
t
t
a
e
b
h
e pe a
sum total of all the numbers. Don’t forget t
p
W
ǩ 0DNH D ȌIWK QHZ QXPEHU E\ DGGLQJ WRJHWKHU WKH e o i ri
WKH
W
ǩ ǩ
RJHWKHU
E\
QH
DGGLQJ
E
Z
QXPEHU
H
E
K
H
D
0DN
D
ȌIWK
G
D
you can use a pen and paper for this trick
e
e
w
r
m
u
w
d

third and fourth numbers and write it below them.
n
ǩ .HHS JRLQJ LQ WKH VDPH IDVKLRQ XQWLO WKHUH LV
ǩ H J J W V V R Q W H
a column of ten numbers.
a l l n f t t m b r
S e
Step 2
A y r e t h b s
Ask your friend to show you the list of numbers.
an
c
ou
add
him
h
h
her
that
y
y
or
m
number

T T
s
Tell him or her that you can add the numbers
r
the

ell
r
c
ogether quick
t together quicker using a pen and paper than
t
n
a
a
n
r
er using a pen and paper than
i
r
r
he or she can using a calculator.
h
a
e
s
l
r
99
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