Bài 1: 

18/27=2/3

35/25=7/5

54/72=3/4

78/66=13/11

92/100=23/25

75/125=3/5

126/165=42/55

150/300=1/2

1717/1515=17/15

2/3       

 7/5  

3/4

13/11

23/25

3/5

42/55

1/2

17/15

\(\dfrac{1717}{1515}=\dfrac{1717:101}{1515:101}=\dfrac{17}{15}\)

ấy dấu gạch kiểu gì thế

\(\dfrac{75}{100}=\dfrac{3}{4};\dfrac{63}{126}=\dfrac{1}{2}\\ \dfrac{36}{27}=1\dfrac{1}{3};\dfrac{81}{54}=1\dfrac{1}{2};\dfrac{105}{405}=\dfrac{7}{27}\)

\(\dfrac{3}{4}\)

\(\dfrac{1}{2}\)

\(\dfrac{4}{3}\)

\(\dfrac{3}{2}\)

\(\dfrac{4}{15}\)

75/100= 75:25/100:25= 3/4

63/126= 63:63/126:63= 1/2

36/27= 36:6/27:9= 4/3

81/54= 81:27/54:27= 3/2

108/405= 108:27/404:27=4/15

\(\frac{1414+1515+1616+1717+1818+1919}{2000+2121+2222+2323+2424+2525}\)

\(=\frac{101.\left(14+15+16+17+18+19\right)}{101.\left(20+21+22+23+24+25\right)}\)

\(\frac{14+15+16+17+18+19}{20+21+22+23+24+25}=\frac{99}{135}=\frac{11}{15}\)

L_I_K_E NHA

căm ơn mấy bạn nhak

\(\frac{11}{15}\)

\(\frac{54}{11}\times\frac{121}{24}< n< \frac{100}{21}\div\frac{25}{126}\Leftrightarrow\frac{99}{4}< n< 24\Leftrightarrow24,75< n< 24\)\(24\)

Vậy không có giá tri của n

tại sao?

sao con cặk

\(\frac{1515}{6363}\times\frac{212121}{606060}-\frac{9}{54}\)

=\(\frac{1}{12}-\frac{9}{54}\)

=\(\frac{9}{108}-\frac{18}{108}\)

=\(-\frac{1}{12}\)

HOK TỐT

=\(\frac{-1}{12}\)

học 

tốt 

nhA

đậu xanh trả lời nhanh nhận 1 đống quà

Câu 2

\(\dfrac{4}{5}\); \(\dfrac{6}{7};\dfrac{3}{10};\dfrac{21}{70};\dfrac{30}{35};\dfrac{44}{55};\dfrac{100}{125};\dfrac{33}{100};\dfrac{54}{63}\)

Các phân số bằng nhau là:

 \(\dfrac{4}{5}=\dfrac{44}{55}=\dfrac{100}{125}\)

\(\dfrac{6}{7}=\dfrac{30}{35}=\dfrac{54}{63}\)

\(\dfrac{3}{10}=\dfrac{21}{70}=\dfrac{33}{100}\)

Mọi người ơi giải giúp mình câu 2 đi ạ