Question

Giải rõ ràng ra giúp mik với

Answer 1

bài 1

a)\(=\dfrac{6}{21}+\dfrac{7}{21}=\dfrac{13}{21}\)

b)\(=\dfrac{9}{15}-\dfrac{5}{15}=\dfrac{4}{15}\)

c)\(=\dfrac{13}{4}\times\dfrac{1}{5}=\dfrac{13}{20}\)

d)\(=\dfrac{6}{23\times6\times3}=\dfrac{1}{69}\)

Answer 2

bài 1, 

2/7+1/3=13/21

3/5-1/3=4/15

13/4:5=13/20

6/23x1/18=1/69

Answer 3

bài 1 :

a) = 13/21

b) = 4/15

c) = 13/20

d) = 1/69

bài 2 :

a) x = 5/12 - 1/3

x = 1/12

b) x = 2/5 x 7/4

x = 7/10

Answer 4

bài 2

a)\(x=\dfrac{5}{12}-\dfrac{1}{3}=\dfrac{5}{12}-\dfrac{4}{12}=\dfrac{1}{12}\)

b)\(x=\dfrac{2}{5}\times\dfrac{7}{4}=\dfrac{14}{20}=\dfrac{7}{10}\)