Hỗn số (tiếp theo)

a: \(=\dfrac{4}{3}\cdot\dfrac{5}{4}\cdot\dfrac{6}{5}\cdot\dfrac{7}{6}\cdot\dfrac{8}{7}\cdot\dfrac{9}{8}=\dfrac{9}{3}=3\)

b: \(=\dfrac{4}{3}:\dfrac{5}{4}:\dfrac{6}{5}:\dfrac{7}{6}:\dfrac{8}{7}:\dfrac{9}{8}\)

\(=\dfrac{16}{27}\)

a, \(=\dfrac{13}{5}+\dfrac{5}{4}.\dfrac{8}{3}=\dfrac{13}{5}+\dfrac{10}{3}=\dfrac{89}{15}\)

b, \(=\dfrac{36}{7}-\dfrac{14}{5}:\dfrac{6}{5}=\dfrac{36}{7}-\dfrac{7}{3}=\dfrac{59}{21}\)

c, \(=\dfrac{17}{4}-\dfrac{21}{8}.\dfrac{16}{39}=\dfrac{17}{4}-\dfrac{42}{39}=\dfrac{165}{52}\)

a. \(2\dfrac{3}{5}+1\dfrac{1}{4} . 2\dfrac{2}{3}=\dfrac{13}{5}+\dfrac{5}{4} . \dfrac{8}{3}=\dfrac{13}{5}+\dfrac{10}{3}=\dfrac{89}{15}\)

b. \(5\dfrac{1}{7}-2\dfrac{4}{5} : 1\dfrac{1}{5}=\dfrac{36}{7}-\dfrac{14}{5} : \dfrac{6}{5}=\dfrac{36}{7}-\dfrac{7}{3}=\dfrac{59}{21}\)

c. \(4\dfrac{1}{4}-2\dfrac{5}{8} . \dfrac{16}{39}=\dfrac{17}{4}-\dfrac{21}{8} . \dfrac{16}{39}=\dfrac{17}{4}-\dfrac{14}{13}=\dfrac{165}{52}\)

a) \(2\dfrac{3}{5}+1\dfrac{1}{4}\times2\dfrac{2}{3}\)

\(=\dfrac{13}{5}+\dfrac{5}{4}\times\dfrac{8}{3}\)

\(=\dfrac{13}{5}+\dfrac{10}{3}\)

\(=\dfrac{89}{15}\)

b) \(5\dfrac{1}{7}-2\dfrac{4}{5}:1\dfrac{1}{5}\)

\(=\dfrac{36}{7}-\dfrac{14}{5}:\dfrac{6}{5}\)

\(=\dfrac{36}{7}-\dfrac{7}{3}\)

\(=\dfrac{59}{21}\)

c) \(4\dfrac{1}{4}-2\dfrac{5}{8}\times\dfrac{16}{39}\)

\(=\dfrac{17}{4}-\dfrac{21}{8}\times\dfrac{16}{39}\)

\(=\dfrac{17}{4}-\dfrac{14}{13}\)

\(=\dfrac{165}{52}\)

a, \(=\dfrac{5}{2}+\dfrac{15}{4}=\dfrac{25}{4}\)

b, \(=3-\dfrac{7}{5}=\dfrac{8}{5}\)

c, \(=\dfrac{23}{5}.\dfrac{100}{46}=\dfrac{20}{2}=10\)

d, \(=\dfrac{72}{17}:9=\dfrac{8}{17}\)

a) S

b) S

c) Đ

d) Đ

e) S

g)S

a. Sai
b. Sai
c. Đúng 
d. Đúng
e. Sai
g. Sai

a) Do  \(\dfrac{2}{5}=\dfrac{4}{10}\)

\(\Rightarrow3\dfrac{2}{5}=3\dfrac{4}{10}\)

Chọn C

b) \(5\dfrac{3}{4}=\dfrac{5\times4+3}{4}=\dfrac{23}{4}\)

Chọn C

a: Chọn C

b: Chọn C

\(=>C\)

\(3\dfrac{2}{5}=3\dfrac{4}{10}=>\dfrac{4}{10}=\dfrac{4}{10}\)

-------------------

\(=>5\dfrac{3}{4}=\dfrac{23}{4}mà\dfrac{23}{4}=\dfrac{23}{4}nên.5\dfrac{3}{4}=\dfrac{23}{4}\)

Gọi các số cần tìm là `x`

`9/x xx 5 = 4 1/2`

`9/x xx 5 = 9/2`

`9/x = 9/2 : 5`

`9/x = 9/10`

`=> x = 10`

`5/x : 2 = 1 1/4`

`5/x : 2 = 5/4`

`5/x = 5/4 xx 2`

`5/x = 5/2`

`=>x  = 2`

\(\dfrac{9}{10}x5=4\dfrac{1}{2}\)

\(\dfrac{5}{2}:2=1\dfrac{1}{4}\)

\(2\dfrac{3}{5}+3\dfrac{2}{3}=\dfrac{13}{5}+\dfrac{11}{3}=\dfrac{39}{15}+\dfrac{55}{15}=\dfrac{94}{15}\)

\(4\dfrac{1}{2}-2\dfrac{2}{3}=\dfrac{9}{2}-\dfrac{8}{3}=\dfrac{27}{6}-\dfrac{16}{6}=\dfrac{11}{6}\)

\(1\dfrac{3}{4}\times2\dfrac{2}{3}=\dfrac{7}{4}\times\dfrac{8}{3}=\dfrac{56}{12}=\dfrac{14}{3}\)

\(2\dfrac{3}{4}:1\dfrac{1}{3}=\dfrac{11}{4}:\dfrac{4}{3}=\dfrac{11}{4}\times\dfrac{3}{4}=\dfrac{33}{16}\)

1 con cá nặng:

5/4:2=5/8(kg)

Trọng lượng tất cả là;

2*5/4+4*5/2+5*5/8=125/8(kg)

`3 2/5 = 17/5`

`3 1/2 = 7/2`

`17/5 = 34/10`

`7/2 = 35/10`

`35 > 34` hay `7/2 > 17/5 => 3 2/5 < 3 1/2`

`9 6/8 = 9 3/4 = 39/4`

`9 21/28 = 9 3/4 = 39/4`

`39/4 =  39/4` hay `9 6/8 = 9 21/28`

`1/8 xx 2/11 + 2 3/11 xx 1/8 + 6/11 xx 1/8 `

`= 1/8 xx 2/11 + 25/11 xx 1/8 + 6/11 xx 1/8`

`= 1/8 xx ( 2/11 + 25/11 + 6/11)`

`= 1/8 xx 33/11`

`= 1/8 xx 3`

`= 3/8`