1. A

2. C

3. C

a)6

b,-7

c)15

d)-4

e)20

a) \(\dfrac{1}{2}\)=\(\dfrac{6}{12}\)       b) \(\dfrac{-7}{8}\)=\(\dfrac{-28}{32}\)      c)\(\dfrac{3}{4}\)=\(\dfrac{15}{20}\)       d) \(\dfrac{-4}{9}\)=\(\dfrac{-16}{36}\)

e) \(\dfrac{3}{4}\)=\(\dfrac{15}{20}\)

HỌC TỐT

a) \(\dfrac{2}{5}\times?=\dfrac{3}{10}\)

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

b) \(\dfrac{1}{8}:?=\dfrac{1}{5}\)

\(?=\dfrac{1}{8}:\dfrac{1}{5}=\dfrac{5}{8}\)

a: Phân số cần tìm là: \(\dfrac{3}{10}:\dfrac{2}{5}=\dfrac{3}{10}\cdot\dfrac{5}{2}=\dfrac{15}{20}=\dfrac{3}{4}\)

b: Phân số cần tìm là \(\dfrac{1}{8}:\dfrac{1}{5}=\dfrac{5}{8}\)

a)\(\dfrac{7}{5}\)

b)\(\dfrac{11}{4}\)

\(1\dfrac{2}{5}=\dfrac{7}{5}=\dfrac{14}{10}\)

\(2\dfrac{3}{4}=\dfrac{11}{4}=\dfrac{275}{100}\)

\(a,1\dfrac{2}{5}=\dfrac{7}{5}\)

\(b,2\dfrac{5}{4}=\dfrac{13}{4}\)

`2/3 + 5/4 + 2/3 xx 4/5 = 2/3 xx (5/4+4/5)`

2 phần 3 nhé

a ( ....< ....)

b( ....<....)

a <

b <

tick cho mk nha

a: \(\dfrac{2}{8}=\dfrac{1}{4}\)

\(\dfrac{4}{8}=\dfrac{1}{2};\dfrac{2}{4}=\dfrac{1}{2}\)

b: \(\dfrac{1}{2}=\dfrac{2}{4}=\dfrac{3}{6}=\dfrac{4}{8}=\dfrac{6}{12}\)

\(\dfrac{1}{4}=\dfrac{2}{8}=\dfrac{3}{12}=\dfrac{4}{16}=\dfrac{6}{24}\)

\(\dfrac{3}{4}=\dfrac{6}{8}=\dfrac{9}{12}=\dfrac{12}{16}\)

a)\(4\dfrac{2}{5}:2=\dfrac{22}{5}.\dfrac{1}{2}=\dfrac{11}{5}=2\dfrac{1}{5}\)

b)\(4\dfrac{2}{5}:2=\left(4+\dfrac{2}{5}\right):2=2+\dfrac{1}{5}=2\dfrac{1}{5}\)