Question

[Edogawa Conan]

Tính nhanh:

1/10+2/20+3/30+4/40+5/50+6/60+7/70+8/80+9/90=?

Answer 1

[Trà My]

\(\frac{1}{10}+\frac{2}{20}+\frac{3}{30}+\frac{4}{40}+\frac{5}{50}+\frac{6}{60}+\frac{7}{70}+\frac{8}{80}+\frac{9}{90}\)

\(=\frac{1}{10}+\frac{1}{10}+\frac{1}{10}+\frac{1}{10}+\frac{1}{10}+\frac{1}{10}+\frac{1}{10}+\frac{1}{10}+\frac{1}{10}\)

\(=\frac{9}{10}\)

Answer 2

[Nguyễn Hoàng Việt]

1/10=1/10 ; 2/20=1/10 .......9/90=1/10

1/10*10 =10/10=1