You are being pro­vid­ed with a book chap­ter by chap­ter. I will request you to read the book for me after each chap­ter. After read­ing the chap­ter, 1. short­en the chap­ter to no less than 300 words and no more than 400 words. 2. Do not change the name, address, or any impor­tant nouns in the chap­ter. 3. Do not trans­late the orig­i­nal lan­guage. 4. Keep the same style as the orig­i­nal chap­ter, keep it con­sis­tent through­out the chap­ter. Your reply must com­ply with all four require­ments, or it’s invalid.
I will pro­vide the chap­ter now.

YOU CAN COUNT ON IT
 
�       The largest known prime num­ber has 24,862,048 dig­its when writ­ten
in base 10. It was “dis­cov­ered” by Patrick Laroche in 2018.
 
�            The con­cept of zero seems so sim­ple, but few pre-mod­ern peo­ple
devel­oped it. The Indi­ans were the first peo­ple to devel­op the zero as
a writ­ten dig­it maybe in the 7th cen­tu­ry CE but pos­si­bly ear­li­er.
 
�       In geom­e­try, a poly­gon is any shape that has a limited/finite num­ber
of straight lines that close togeth­er to form the shape. Tri­an­gles and
squares are poly­gons, but cir­cles are not because their lines are not
straight.
 
�       If you mul­ti­ple the num­ber nine by any num­ber, and add all the dig­its
of the sum, you’ll always get nine. For instance, 127x9=1,143;
1+1+4+3=9. It’s true every time!
 
�            The ancient Egyp­tians and ancient Egyp­tians had sym­bols for and
used frac­tions in their math, but they did so with­out the con­cept of
zero.
 
�            “Com­bi­na­torics” refers to any type of count­ing. Although it sounds
sim­ple enough, com­bi­na­torics includes prob­a­bil­i­ty, finite geom­e­try,
and design the­o­ry.
 
�            The study known as “game the­o­ry” com­bines math with social
sci­ence, log­ic, and com­put­er sci­ence. It’s gen­er­al­ly used to deter­mine
what a per­son­’s loss­es or gains will be in a par­tic­u­lar sce­nario.
 
�       The ancient Greek math­e­mati­cian, Pythago­ras (ca. 570–495 BCE), is
best known for his the­o­rem — a2+b2=c2 — but he was also a mys­tic who
led a com­mune.
 
�            “I’ll be back in a jiffy” actu­al­ly refers to time mea­sure­ment. In
com­put­er ani­ma­tion, a jiffy rep­re­sents 1/100th-of-a-sec­ond, while in
elec­tron­ics it’s a peri­od of an alter­nat­ing cur­rent  pow­er cycle;  either
1/60 or 1/50 of a sec­ond.
 
�            A “quant” is a per­son who uses quan­ti­ta­tive analy­sis in finan­cial
invest­ing. The invest­ment meth­ods quants use is often called
quan­ti­ta­tive invest­ment man­age­ment.
 
�            Eco­nom­ics is the study of the exchange of goods, ser­vices, and
com­modi­ties. Although you don’t have to be a math whiz to be an
econ­o­mist, the study does require some alge­bra, cal­cu­lus, and
sta­tis­tics.
 
�            A pic­ture with­in a pic­ture, etc., is known as the “Droste effect.”
The­o­ret­i­cal­ly, this could con­tin­ue infi­nite­ly but in prac­ti­cal­i­ty, it only
con­tin­ues as long the image can be seen.
 
�            The dou­ble-entry sys­tem of book­keep­ing or account­ing is often
attrib­uted to the Flo­ren­tine mer­chant, Amati­no Manuc­ci. His dou­ble-
entry accounts from 1299–1300 are the ear­li­est on record.
 
�            The oppo­site sides of tra­di­tion­al dice always add up to sev­en. You
can throw the dice as much as you want, but it’s always the case.
 
�            Com­plex analy­sis is a type of math that con­cerns how com­plex
num­bers func­tion. Mechan­i­cal, elec­tri­cal, and nuclear engi­neer­ing all
use com­plex analy­sis, such as deter­min­ing how to launch a satel­lite.
 
�            Did you know that you can always cut through a ham and cheese
sand­wich so that the remain­ing halves are exact­ly the same size? This
is called the ham sand­wich the­o­rem.
 
�            There are 52 cards in a tra­di­tion­al deck of cards and 52! (Fac­to­r­i­al
52) per­mu­ta­tions of those cards. That num­ber is …