bn có tíc ko zậy ?

Châu Á là châu lục lớn nhất về diện tích và dân số 4.623.940.078 người (cập nhật 30/01/2020 theo số liệu từ Liên Hợp Quốc), có diện tích khoảng 49.7 triệu km2 chiếm hơn 30% phần đất liền trên trái đất.

a,3/5+4/7+2/5+1/7+2/7

= (4/7+1/7+2/7)+(3/5+4/5)

=7/7+5/5

=1+1

=2

b, 1/3+1/6+4/3+2/6+2/3+5/6

=(1/3+4/3+2/3)+(1/6+5/6+2/6)

=7/3+8/6

=7/3+4/3

=11/3

          Bài làm :

Ta có :

\(A=\frac{1}{2}\div\frac{3}{4}+\frac{1}{6}\div\frac{3}{4}=\left(\frac{1}{2}+\frac{1}{6}\right)\div\frac{3}{4}=\frac{8}{9}\)

Bài làm :

\(a,\frac{1}{2}:\frac{3}{4}+\frac{1}{6}:\frac{3}{4}\)

\(=\left(\frac{1}{2}+\frac{1}{6}\right):\frac{3}{4}\)

\(=\frac{2}{3}:\frac{3}{4}\)

\(=\frac{8}{9}\)

Bài làm 

có phải là :

1/2 : 3/4 + 1/6 : 3/4

= ( 1/2 + 3/4 ) : 3/4

= 2/3 : 3/4

=8/9

bài này bạn tự làm được mà, có cần nhất thiết mà hỏi lên mạng đâu ???

a)\(\dfrac{2}{3}.\dfrac{4}{5}+\dfrac{1}{3}.\dfrac{4}{5}=\left(\dfrac{2}{3}+\dfrac{1}{3}\right).\dfrac{4}{5}=1.\dfrac{4}{5}=\dfrac{4}{5}\)

b)\(\dfrac{2}{3}.\dfrac{4}{5}-\dfrac{1}{3}.\dfrac{4}{5}=\left(\dfrac{2}{3}-\dfrac{1}{3}\right).\dfrac{4}{5}=\dfrac{1}{3}.\dfrac{4}{5}=\dfrac{4}{15}\)

a) \(\dfrac{2}{3}\times\dfrac{4}{5}+\dfrac{1}{3}\times\dfrac{4}{5}=\dfrac{4}{5}\times\left(\dfrac{2}{3}+\dfrac{1}{3}\right)=\dfrac{4}{5}\times1=\dfrac{4}{5}\)

b) \(\dfrac{2}{3}\times\dfrac{4}{5}-\dfrac{1}{3}\times\dfrac{4}{5}=\dfrac{4}{5}\times\left(\dfrac{2}{3}-\dfrac{1}{3}\right)=\dfrac{4}{5}\times\dfrac{1}{3}=\dfrac{4}{15}\)

c) \(\dfrac{1}{2}:\dfrac{3}{4}+\dfrac{1}{6}:\dfrac{3}{4}=\dfrac{1}{2}\times\dfrac{4}{3}+\dfrac{1}{6}\times\dfrac{4}{3}=\dfrac{4}{3}\times\left(\dfrac{1}{2}+\dfrac{1}{6}\right)=\dfrac{4}{3}\times\dfrac{2}{3}=\dfrac{8}{9}\)

d) \(\dfrac{1}{2}:\dfrac{3}{4}-\dfrac{1}{6}:\dfrac{3}{4}=\dfrac{1}{2}\times\dfrac{4}{3}-\dfrac{1}{6}\times\dfrac{4}{3}=\dfrac{4}{3}\left(\dfrac{1}{2}-\dfrac{1}{6}\right)=\dfrac{4}{3}\times\dfrac{1}{3}=\dfrac{4}{9}\)

c)\(\dfrac{1}{2}:\dfrac{3}{4}+\dfrac{1}{6}:\dfrac{3}{4}=\dfrac{1}{2}.\dfrac{4}{3}+\dfrac{1}{6}.\dfrac{4}{3}=\left(\dfrac{1}{2}+\dfrac{1}{6}\right).\dfrac{4}{3}=\dfrac{2}{3}.\dfrac{4}{3}=\dfrac{8}{9}\)

d)\(\dfrac{1}{2}:\dfrac{3}{4}-\dfrac{1}{6}:\dfrac{3}{4}=\dfrac{1}{2}.\dfrac{4}{3}-\dfrac{1}{6}.\dfrac{4}{3}=\left(\dfrac{1}{2}-\dfrac{1}{6}\right).\dfrac{4}{3}=\dfrac{1}{3}.\dfrac{4}{3}=\dfrac{4}{9}\)

1/2 + 1/3 + 1/4 + 1/5 + 4/5 + 3/4 + 2/3 + 1/2

= (1/2 + 1/2) + (1/3 + 2/3) + (1/4 + 3/4) + (1/5 + 4/5)

= 1 + 1 + 1 + 1

= 4

\(\frac{2}{3}\times\frac{4}{5}+\frac{4}{5}\times\frac{1}{2}+\frac{4}{5}\times\frac{1}{6}\)

\(=\left(\frac{2}{3}+\frac{1}{2}+\frac{1}{6}\right)\times\frac{4}{5}\)

\(=\frac{4}{3}\times\frac{4}{5}\)

\(=\frac{16}{15}\)

\(\left(1-\frac{1}{2}\right).\left(1-\frac{1}{3}\right).\left(1-\frac{1}{4}\right).\left(1-\frac{1}{5}\right)\)

\(=\frac{1}{2}.\frac{2}{3}.\frac{3}{4}.\frac{4}{5}\)

\(=\frac{1}{3}.\frac{3}{4}.\frac{4}{5}\)

\(=\frac{1}{3}.\frac{3}{5}\)

\(=\frac{1}{5}\)

ủng hộ tớ nha

mk ko biết xin lỗi bạn nha!!!

mk ko biết xin lỗi bạn nha!!!

mk ko biết xin lỗi bạn nha!!!

mk ko biết xin lỗi bạn nha!!!

= 3/2 + 2/3 + 2/4 + 2/5

= (6/4 + 2/4) + (2/3 + 2/5)

= 8/4 + 16/ 15 

= 46/15

=46/15

1+2+3+4+5+6+7+8+9

=[1+9]+[2+8]+...+[4+6]+5

=10*4+5

=45

= (1+9)+(2+8)+(3+7)+(4+6)+5

= 10+10+10+10+5

=45

=(1+9)+(2+8)+(3+7)+(4+6)+5=10+10+10+10+5=45