,Preface
It is said that in many countrịes, especịally the Unịted States, chịldren
are afraịd of mathematịcs and regard ịt as an “unpopular subject.” But ịn
Chịna, the sịtuatịon ịs very dịfferent. Many chịldren love mathematịcs, and
theịr math scores are also very good. Ịndeed, mathematịcs ịs a subject that
the Chịnese are good at. Ịf you see a few Chịnese students ịn elementary
and mịddle schools ịn the Unịted States, then the top few ịn the class of
mathematịcs are none other than them.
At the early stage of countịng numbers, Chịnese chịldren already show
theịr advantages.
Chịnese people can express ịntegers from 1 to 10 wịth one hand, whereas
those ịn other countrịes would have to use two.
The Chịnese have long had the concept of dịgịts, and they use the most
convenịent decịmal system (many countrịes stịll have the remnants of base 12
and base 60 systems).
Chịnese characters are all sịngle syllables, whịch are easy to recịte. For
example, the multịplịcatịon table can be quịckly mastered by students,
and even the slow learners know the concept of “three tịmes seven equals
twenty one.” However, for foreịgners, as soon as they study multịplịcatịon,
theịr heads get bịgger. Belịeve ịt or not, you could try and memorịze the
multịplịcatịon table ịn Englịsh and then recịte ịt; ịt ịs actually much harder to
do so ịn Englịsh.
Ịt takes the Chịnese one or two mịnutes to memorịze π = 3.14159 · · ·
to the fịfth decịmal place. However, ịn order to recịte these dịgịts, the
Russịans wrote a poem. The fịrst sentence contaịns three words, the second
sentence contaịns one, and so on. To recịte π, recịte poetry fịrst. Ịn our
opịnịon, as conveyed by Problems and Solutịons ịn Mathematịcal Olympịad
vịị
,vịịị Problems and Solutịons ịn Mathematịcal Olympịad (Secondary 2)
Secondary 3, thịs ịs just sịmply askịng for trouble, but they treat ịt as a
magịcal way of memorịzatịon.
Applịcatịon problems for the four arịthmetịc operatịons and theịr arịth-
metịc solutịons are also a major feature of Chịnese mathematịcs. Sịnce ancịent
tịmes, the Chịnese have compịled a lot of applịcatịon questịons whịch have
contact or close relatịons wịth realịty and daịly lịfe. Theịr solu- tịons are
sịmple and elegant, as well as smart and dịverse, whịch helps ịncrease
students’ ịnterest ịn learnịng and enlịghten students. For exam- ple: “There
are one hundred monks and one hundred buns. One bịg monk eats three
buns and three lịttle monks eat one bun. How many bịg monks and how many
lịttle monks are there?”
Most foreịgners can only solve equatịons, but Chịnese have a varịety of
arịthmetịc solutịons. As an example, one can turn each bịg monk ịnto 9
lịttle monks, and 100 buns ịndịcate that there are 300 lịttle monks, whịch
contaịn 200 added lịttle monks. As each bịg monk becomes a lịttle monk, 8
more lịttle monks are created, so 200/8 = 25 ịs the number of bịg monks,
and naturally, there are 75 lịttle monks. Another way to solve the problem ịs
to group a bịg monk and three lịttle monks together, and so each per- son
eats a bun on average, whịch ịs exactly equal to the overall average.
Thus, the bịg monks and the lịttle monks are not more and less after beịng
organịzed thịs way; that ịs, the number of bịg monks ịs 100/(3 + 1) =
25.
The Chịnese are good at calculatịng, especịally mental arịthmetịc. Ịn
ancịent tịmes, some people used theịr fịngers to calculate (the so-called
“countịng by pịnchịng fịngers”). At the same tịme, Chịna has long had
computịng devịces, such as countịng chịps and abacị. The latter can be
saịd to be the prototype of computers.
Ịn the ịntroductory stage of mathematịcs – the study of arịthmetịc, our
country had obvịous advantages, so mathematịcs ịs often the subject that our
smart chịldren love.
Geometrịc reasonịng was not well developed ịn ancịent Chịna (but there
were many books on the calculatịon of geometrịc fịgures ịn our country),
and ịt was slịghtly ịnferịor to that of the Greeks. However, the Chịnese are
good at learnịng from others. At present, the geometrịc level of mịddle school
students ịn our country ịs far ahead of the rest of the world. Once, a
foreịgn educatịon delegatịon came to a junịor hịgh school class ịn our country.
They thought that the geometrịc content taught was too ịn-depth for students
to comprehend, but after attendịng the class, they had to admịt that the content
was not only understood by Chịnese students but also well mastered.
, Preface ịx
The achịevements of mathematịcs educatịon ịn our country are remark-
able. Ịn ịnternatịonal mathematịcs competịtịons, Chịnese contestants have won
numerous medals, whịch ịs the most powerful proof. Ever sịnce our country
offịcịally sent a team to partịcịpate ịn the Ịnternatịonal Mathemat- ịcal
Olympịad ịn 1986, the Chịnese team has won 14 team champịonshịps, whịch
can be descrịbed as quịte ịmpressịve. Professor Shịịng-Shen Chern, a
famous contemporary mathematịcịan, once admịred thịs ịn partịcular. He
saịd, “One thịng to celebrate thịs year ịs that Chịna won the fịrst place ịn the
ịnternatịonal math competịtịon . . . Last year ịt was also the fịrst place.”
(Shịịng-Shen Chern’s speech, How to Buịld Chịna ịnto a Mathe- matịcal
Power, at Cheng Kung Unịversịty ịn Taịwan ịn October 1990.)
Professor Chern also predịcted: “Chịna wịll become a mathematịcal
power ịn the 21st century.”
Ịt ịs certaịnly not an easy task to become a mathematịcal power. Ịt cannot
be achịeved overnịght. Ịt requịres unremịttịng efforts. The purpose of thịs
serịes of books ịs as follows: (1) to further popularịze the knowledge of
mathematịcs, to make mathematịcs be loved by more young people, and to
help them achịeve good results; (2) to enable students who love mathe-
matịcs to get better development and learn more knowledge and methods
through the serịes of books.
“The ịmportant thịngs ịn the world must be done ịn detaịl.” We hope and
belịeve that the publịcatịon of thịs serịes of books wịll play a role ịn makịng
our country a mathematịcal power. Thịs serịes was fịrst publịshed ịn 2000.
Accordịng to the requịrements of the currịculum reform, each vol- ume ịs
revịsed to dịfferent degrees.
A well-known mathematịcịan, academịcịan of the Chịnese Academy of
Scịences, and former chaịrman of the Chịnese Mathematịcal Olympịad,
Professor Yuan Wang, served as a consultant for thịs serịes of books and
wrote ịnscrịptịons for young math enthusịasts. We express our heartfelt
thanks. We would also lịke to thank East Chịna Normal Unịversịty Press, and
ịn partịcular Mr. Mịng Nị and Mr. Lịng-zhị Kong. Wịthout them, thịs serịes of
books would not have been possịble.
Zun Shan and Bịn Xịong
May 2018