\(=14:\left(\frac{14}{3}-\frac{14}{9}\right)+14:\left(\frac{2}{3}+\frac{8}{9}\right)\)

\(=14:\frac{28}{9}+14:\frac{14}{9}\)

\(=\frac{28}{9}+\frac{14}{9}\)

\(=\frac{42}{9}\)

\(14:\left(\frac{14}{3}-\frac{14}{9}\right)+14:\left(\frac{2}{3}+\frac{8}{9}\right)\)

\(=14:\left(\frac{42}{9}-\frac{14}{9}\right)+14:\left(\frac{6}{9}+\frac{8}{9}\right)\)

\(=14:\frac{28}{9}+14:\frac{14}{9}\)

\(=14.\frac{9}{28}+14.\frac{9}{14}\)

\(=14.\left(\frac{9}{28}+\frac{9}{14}\right)\)

\(=14.\left(\frac{9}{28}+\frac{18}{28}\right)\)

\(=14.\frac{27}{28}\)

\(=\frac{378}{28}\)

\(=\frac{27}{2}\)

= 14 : ( 14/3 - 14/9 ) + 14 : ( 2/3 + 8/9 ) 

= 14 : 28/9 +  14 : 14/9 

= 14 * 9/28 + 14 * 9/14 

= 14 * ( 9/28 + 9/14 ) 

= 14 * 27/28 

= 27/2 

Ta có:

A=\(14:\left(\frac{14}{3}-\frac{14}{5}\right)+14:\left(\frac{2}{3}+\frac{8}{9}\right)\)

\(=14:\left(\frac{14}{3}-\frac{14}{5}+\frac{2}{3}+\frac{8}{9}\right)\)

\(=14:\left(\frac{42+6+8}{3}-\frac{14}{5}\right)\)

\(=14:\left(\frac{56}{3}-\frac{14}{5}\right)\)

\(=14:\left(\frac{280-42}{15}\right)=14:\left(\frac{238}{15}\right)=14\cdot\frac{15}{238}=\frac{210}{238}\)

ko biết có tính sai chỗ nào ko

\(\frac{2}{7}\)+ \(\frac{5}{14}\)+\(\frac{1}{7}\)+ \(\frac{3}{14}\)=\(\frac{4}{14}\)+\(\frac{5}{14}\)+\(\frac{2}{14}\)+\(\frac{3}{14}\)=\(\frac{14}{14}\)=1

469x281+489x719=469x281+(469+20)x719=469x281+469x719+20x719=469x(281+719)+1438=469x1000+1438=469000+1438=470438

a\(\frac{2}{5}\)+\(\frac{5}{14}\)+\(\frac{1}{7}\)+\(\frac{3}{14}\)=\(\frac{53}{70}\)+\(\frac{1}{7}\)=\(\frac{9}{10}\)+\(\frac{3}{14}\)=\(\frac{39}{35}\)

b\(\frac{1995.1997-1}{1996.1995+1994}\)=3984008001

c    469x281+489x719

=(489-469)x(281+719)

=20x1000

=20000

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

2) \(\frac{5+x}{8}=\frac{14}{16}\)

\(\Rightarrow\left(5+x\right).16=8.14\)

\(\Rightarrow80+16x=112\)

\(\Rightarrow16x=112-80\)

\(\Rightarrow16x=32\)

\(\Rightarrow x=32\div16\)

\(\Rightarrow x=2\)

đưa hết hỗn số về dạng phân số rồi quy đồng bình thường ạ !

Hoàng_Linh_Nga làm đc thì làm nhé.

Giải:

\(2\frac{1}{6}+3\frac{2}{3}\)

\(=\frac{13}{12}+\frac{11}{9}\)

\(=\frac{249}{108}\)

\(4\frac{3}{4}-3\frac{5}{6}\)

\(=\frac{19}{16}-\frac{23}{18}\)

\(=\frac{342}{288}-\frac{368}{288}\)

\(=\frac{-26}{288}\)xem lại đề đi nhé

\(9\frac{1}{6}\times4\frac{2}{3}\)

\(=\frac{55}{18}\times\frac{15}{12}\)

\(=\frac{825}{216}\)

\(2\frac{5}{7}:\frac{14}{5}\)

\(=\frac{19}{7}:\frac{14}{5}\)

\(=\frac{95}{98}\)

\(3\frac{1}{2}=\frac{7}{2};4\frac{5}{7}=\frac{33}{7}\)

\(3\frac{1}{2}+4\frac{5}{7}-\frac{5}{14}\)

\(=\frac{7}{2}+\frac{33}{7}-\frac{5}{14}\)

\(=\frac{49}{14}+\frac{66}{14}-\frac{5}{14}\)

\(=\frac{115}{14}-\frac{5}{14}\)

\(=\frac{110}{14}=\frac{55}{7}\)

\(\frac{4}{5}+\frac{1}{5}=\frac{5}{5}=1\)
\(\frac{14}{12}+\frac{2}{3}=\frac{14}{12}+\frac{8}{12}=\frac{22}{12}=1\frac{10}{12}\)
4/5 + 1/5
= 5/5
= 1

14/12 + 2/3
= 14/12 + 8/12
= 22/12

4/5 + 1/5
= 5/5
= 1

14/12 + 2/3
= 14/12 + 8/12
= 22/12

1 hoặc 5/5

11/6

nha bn

k mk nha bn

Ai nhanh được k nha :))

Trả lời 

\(A=\frac{11}{12+13}+\frac{12}{13+14}+\frac{1}{14+15}\)

Hay 

\(A=\frac{11}{12+13}+\frac{12}{13+14}+\frac{13}{14+15}\)

mong xem lại hộ cái