"Everyday Mathematics" serial 53: February 21

2 month 21 Japan XXI

Mathematical maxims

A person is like a score , The molecule is his real self , The denominator is his self-evaluation . The larger the denominator , The smaller the score .—— Tolstoy （Tolstoy）

Math exercises

Arithmetic mean and ratio ：54,x,y,43 and 21 The arithmetic mean of is 40.4.x and y The ratio is 6. seek x and y Value .

Ancient and Modern Commentaries

《 Old Testament 》 Many involve large quantities . For a specific number , Not named , It's an analogy . For example, in Genesis （Genesis）22:17 in , A number is compared to the stars in the sky and the sand on the earth ; In the book of Kings （Kings）3:8 in , We found the phrase “ Countless ”. When using thousands of terms （a thousand thousands） When , The largest number of names appears in the annals of the past dynasties （2 Chronicles） in . Millions of words （million） It first appeared in the middle ages （Middle Ages） Late stage of . When thousands became a common expression used by Medieval merchants , Terminology millions （million） From the Italian word milione Created , It means more than a thousand .

Tolstoy

Lev · Nikolayevich · Tolstoy （Лев Николаевич Толстой;1828 year 9 month 9 Japan －1910 year 11 month 20 Japan ）,19 Russian critical realist writers in the middle of the th century 、 thinker , philosopher , including 《 War and Peace 》、《 Anna · Karenina 》、《 resurrection 》 etc. .

Tolstoy was born into a noble family ,1840 He joined Kazan University in ,1847 Retired in