Rút gọn:

\(\frac{15}{30}=\frac{2}{3}\)

\(\frac{48}{64}=\frac{3}{4}\)

\(\frac{34}{85}=\frac{2}{5}\)

Quy đồng:

\(\frac{40}{60}=\frac{45}{60}=\frac{24}{60}\)

1, 1/2

2, 3/4

3, 2/5

\(a,\dfrac{52}{32}=\dfrac{13}{8}\\ \dfrac{55}{65}=\dfrac{11}{13}\\ MSC:104\\ =>\dfrac{13}{8}=\dfrac{13.13}{8.13}=\dfrac{169}{104}\\ \dfrac{11}{13}=\dfrac{11.8}{13.8}=\dfrac{88}{104}\)

\(b,\dfrac{72}{64}=\dfrac{9}{8}\\ \dfrac{54}{81}=\dfrac{2}{3}\\ MSC:24\\ \dfrac{9}{8}=\dfrac{9.3}{8.3}=\dfrac{27}{24}\\ \dfrac{2}{3}=\dfrac{2.8}{3.8}=\dfrac{16}{24}\\ c,\dfrac{24}{36}=\dfrac{2}{3}\\ \dfrac{12}{30}=\dfrac{2}{5}\\ MSC:15\\ \dfrac{2}{3}=\dfrac{2.5}{3.5}=\dfrac{10}{15}\\ \dfrac{2}{5}=\dfrac{2.3}{3.5}=\dfrac{6}{15}\)

\(d,\dfrac{80}{40}=2\\ \dfrac{45}{63}=\dfrac{5}{7}\\ MSC:7\\ 2=\dfrac{14}{7}\\ e,\dfrac{150}{50}=3\\ \dfrac{100}{200}=\dfrac{1}{2}\\ MSC:2\\ 3=\dfrac{6}{2}\\ f,\dfrac{54}{81}=\dfrac{2}{3}\\ \dfrac{69}{93}=\dfrac{23}{21}\\ MSC:21\\ \dfrac{2}{3}=\dfrac{2.7}{3.7}=\dfrac{14}{21}\)

\(a.\dfrac{52}{32}\text{=}\dfrac{13}{8};\dfrac{55}{65}\text{=}\dfrac{11}{13}\)

\(\dfrac{13.13}{13.8}\text{=}\dfrac{169}{104};\dfrac{11.8}{13.8}\text{=}\dfrac{88}{104}\)

\(c.\dfrac{24}{36}\text{=}\dfrac{2}{3};\dfrac{12}{30}\text{=}\dfrac{2}{5}\)

\(\dfrac{2.5}{3.5}\text{=}\dfrac{10}{15};\dfrac{2.3}{5.3}\text{=}\dfrac{6}{15}\)

\(b.\dfrac{72}{64}\text{=}\dfrac{9.3}{8.3}\text{=}\dfrac{27}{24};\dfrac{54}{81}\text{=}\dfrac{2.8}{3.8}\text{=}\dfrac{16}{24}\)

\(d.\dfrac{80}{40}\text{=}\dfrac{2.63}{63}\text{=}\dfrac{126}{63};\dfrac{45}{63}\)

\(e.\dfrac{150}{50}\text{=}\dfrac{3.2}{2}\text{=}\dfrac{6}{2};\dfrac{100}{200}\text{=}\dfrac{1}{2}\)

\(f.\dfrac{54}{81}\text{=}\dfrac{2.31}{3.31}\text{=}\dfrac{62}{93};\dfrac{69}{93}\)

a) \(...=\dfrac{5}{6}-\dfrac{4}{15}=\dfrac{75}{90}-\dfrac{24}{90}=\dfrac{51}{90}\)

b) \(...=\dfrac{1}{2}-\dfrac{1}{5}=\dfrac{5}{10}-\dfrac{2}{10}=\dfrac{3}{10}\)

\(\dfrac{25}{30}\) - \(\dfrac{4}{15}\) = \(\dfrac{5}{6}\) - \(\dfrac{4}{15}\) = \(\dfrac{17}{30}\)

\(\dfrac{27}{54}\) - \(\dfrac{3}{15}\) = \(\dfrac{1}{2}\) - \(\dfrac{1}{5}\) = \(\dfrac{3}{10}\) 

Bạn tự QĐMS nhé

a . 21/70 = 3/10 ; 56/96 = 7/12 ; 60/72 = 15/18

Mình chỉ làm tới đây thôi .

Tưởng z là ngầu?:)

Tưởng z là ngầu?:)

၁၁မန််ခခခ

`Answer:`

`a)` Ta có:

\(\frac{29-5}{54}=\frac{4}{9}\)

\(\frac{45-54}{33}=-\frac{3}{11}\)

Mẫu chung là `99`

\(\Rightarrow\frac{4}{9}=\frac{4.11}{9.11}=\frac{44}{99}\)

\(\Rightarrow\frac{-3}{11}=\frac{\left(-3\right).9}{11.9}=-\frac{27}{99}\)

`b)` Ta có:

\(\frac{18+14}{18}=\frac{16}{4}\)

\(\frac{26-50}{30}=-\frac{4}{5}\)

Mẫu chung là `45`

\(\Rightarrow\frac{16}{9}=\frac{16.5}{9.5}=\frac{80}{45}\)

\(\Rightarrow-\frac{4}{5}=\frac{\left(-4\right).9}{5.9}=-\frac{36}{45}\)

Câu 1: Rút gọn rồi quy đồng các phân số sau:

9/30;98/80;15/1000

Câu 2: Các phân số sau có bằng nhau hay không?

a) -3/5 và 39/-65

b) -9/27 và -41/123

c) -3/4 và 4/-5

d) 2/-3 và -5/7

Câu 3:

a)25*9-25*17/-8*80-8*10 và 48*12-48*15/-3*270-3*30

b)2^5*7+2^5/2^5*5^2-2^5*3 và 3^4*5-3^6/3^4*13+3^4

Ta có: \(A=\dfrac{3469-54}{6938-108}\)

\(=\dfrac{3469-54}{2\left(3469-54\right)}=\dfrac{1}{2}\)

\(=\dfrac{3}{6}\)

Ta có: \(B=\dfrac{2468-98}{3702-147}\)

\(=\dfrac{2\left(1234-49\right)}{3\left(1234-49\right)}=\dfrac{2}{3}\)

\(=\dfrac{4}{6}\)

\(\dfrac{7}{30}=\dfrac{21}{90};\dfrac{4}{45}=\dfrac{8}{90}\)

b: \(=\dfrac{3}{7}\cdot\dfrac{5}{7}\cdot\dfrac{6}{7}=\dfrac{90}{343}\)

c: \(=\dfrac{4}{9}\cdot\dfrac{5}{9}\cdot\dfrac{3}{7}=\dfrac{20}{189}\)

d: \(=\dfrac{1}{3}\cdot\dfrac{5}{12}\cdot\dfrac{5}{12}=\dfrac{25}{432}\)

d