Page 96 - (DK) How to be a GENIUS?

The mos s st logica a al form of think k k king i involv ves number r rs.
W W When you do simple calculat t t tions, you d don’t t t make
guesses. You figure e e e out t t t t the answers by y applying
logi ical rules to the figures. Mo os s st people e worldwide
ha a av ve devised some way o of f f f counting, an nd most have
deve eloped ways of reasoning with numbers.

systems
Counting s
Age farme er counting
Imagine you are a a Stone A using the e fingers of Calcul l lations
i e you are
sheep. You count to ten u
a a i i
both hands. When you get t to ten, yo ou put a stone You want to build d a wall fro o o om br b i icks.
in. If you reach eight,
b
b
in your lap and start aga eight fing gers: 18. It will be 2 200 bricks long and 12 2 2 2 b
be
gers: 18. This
you have one stone and e tem is ba ased on tens. high, bu u u u ut how many bricks will l l y
bricks s s s
you
is why our counting syst need? It’s easy—yo o o y y u ju ust mul u u tip p p p p ly
12 b by tw w w wo, givin i g g g 24, then a add t t tw
wo
zeroes, giving 2,400 b b bricks. s Most
t
calc l ulations s use tri i i i icks like
a
this: they e e are re re e the basis of f f
ma athemat tical thi h h nk king.
Geometry
Mathematics can describe shapes such
as triangles and pyramids in terms of
d
angles and dimensions. This can be used
s
to measure things like the heights of
mountains. If you know your horizontal
m
dis stance (D) to a mountaintop and
t
a
h
have some way of measuring
you ha v , , , , , , , , , , , ,
e
the anggl le as you look up at it, you
ou
can figuure ou t ho w hi gh ( H) i t is
out how high (H) it is.
( ( (

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