Ta có: \(A=\frac{432143214321}{999999999999}=\frac{4321\times100010001}{9999\times100010001}=\frac{4321}{9999}< \frac{1}{2}\)

\(B=\frac{1212+1212+1212+1212}{1919+1919+1919+1919}=\frac{1212\times4}{1919\times4}=\frac{1212}{1919}=\frac{12\times101}{19\times101}=\frac{12}{19}>\frac{1}{2}\)

Do:\(A< \frac{1}{2}< B\Rightarrow A< B\)

\(\frac{121212+12121212-1212}{363636-36363636-3636}=\frac{12\left(111111+11111111-1111\right)}{36\left(111111+11111111-1111\right)}=\frac{12}{36}=\frac{1}{3}\)

1/3 nha

\(\frac{1}{3}\)

chúc ban hk tốt!!(k cho tui nhé)

\(\frac{1919}{1212}+\frac{51515151}{36363636}\)

\(=\)\(\frac{19}{12}+\frac{17}{12}\)

\(=\frac{36}{12}\)

\(=3\)

= \(\frac{19}{12}\)+ \(\frac{17}{12}\)
= \(\frac{36}{12}\)

= \(3\)

\(\frac{121212+12121212-1212}{363636+36363636-3636}\)

\(=\frac{12.10101+12.1010101-12.101}{36.10101+36.1010101-36.101}\)

\(=\frac{12\left(10101+1010101-101\right)}{36\left(10101+1010101-101\right)}\)

\(=\frac{12}{12.3}\)

\(=\frac{1}{3}\)

Ta có: \(\frac{121212+12121212-1212}{363636+36363636-3636}\)

           =\(\frac{12\times\left(10101+1010101-101\right)}{36\times\left(10101+1010101-101\right)}\)

           =\(\frac{12}{36}\)

           =\(\frac{1}{3}\)

\(\frac{121212+12121212-1212}{363636+36363636-3636}\)

\(=\frac{121212+12121212-1212}{3\times121212+3\times12121212-3\times1212}\)

\(=\frac{121212+12121212-1212}{3\times\left(121212+12121212-1212\right)}\)

\(=\frac{1}{3}\)

_Chúc bạn học tốt_

1919/1212+51515151/36363636

=19/12+51/36

=3

bang 3

3 nha bn

\(A=\frac{121212}{363636}+\frac{1212}{3636}\)

\(=\frac{1}{3}+\frac{1}{3}=\frac{2}{3}\)

#)Giải :

\(\frac{121212}{363636}=\frac{121212:10101}{363636:10101}=\frac{12}{36}=\frac{1}{3}\)

\(\frac{1212}{3636}=\frac{1212:101}{3636:101}=\frac{12}{36}=\frac{1}{3}\)

\(\Rightarrow A=\frac{1}{3}+\frac{1}{3}=\frac{2}{3}\)

1212/1515 = 4/5

363636/545454 = 2/3

~hok tốt~

#Trang#

a)1212/1515=4/5.Cả tử và mẫu chia cho 303

b)363636/545454=2/3.Cả tử và mẫu chia cho 181818

\(a,\frac{1212}{1515}=\frac{12.101}{15.101}=\frac{12}{15}\)

\(b,\frac{363636}{545454}=\frac{36.10101}{54.10101}=\frac{36}{54}\)