Question

Tìm y, biết:                        

a. y = 4/5 - 3/4                b. y/7 = 7/8 - 25/56     c. y + 7/12 = 17/18 - 1/9   d. y = 7/8 : 3/5           e. y : 4/5 = 1/2 : 6/5

M.n giải giúp e bài toán này vs, e cảm ơn m.n nhiều

 

 

 

 

 

 

 

 

Answer 1

a) y = \(\frac{4}{5}-\frac{3}{4}\)

\(\Rightarrow y=\frac{16}{20}-\frac{15}{20}\)

\(\Rightarrow y=\frac{1}{20}\)

b)\(\frac{y}{7}=\frac{7}{8}-\frac{25}{26}\)

\(\Rightarrow\frac{y}{7}=-\frac{9}{104}\)

\(\Rightarrow y=\frac{-9}{104}.7\)

\(\Rightarrow y=\frac{-63}{104}\)

c) y \(+\frac{7}{12}=\frac{17}{18}-\frac{1}{9}\)

\(\Rightarrow y+\frac{7}{12}=\frac{15}{18}=\frac{5}{6}\)

\(\Rightarrow y=\frac{5}{6}-\frac{7}{12}\)

\(\Rightarrow y=\frac{3}{12}=\frac{1}{4}\)

d)\(y=\frac{7}{8}:\frac{3}{5}=\frac{7}{8}.\frac{5}{3}=\frac{35}{24}\)

e)\(y:4,5=\frac{1}{2}:\frac{6}{5}\)

\(\Rightarrow y:\frac{9}{2}=\frac{1}{2}.\frac{5}{6}=\frac{5}{12}\)

\(\Rightarrow y=\frac{5}{12}.\frac{9}{2}=\frac{15}{8}\)