x = 11/98

Tim x:

     x X 12  + x X 14  + x X 18   = \(\frac{21}{24}\)

x X (\(\frac{1}{2}+\frac{1}{4}+\frac{1}{8}\)) = \(\frac{21}{24}\)

x X (\(\frac{4}{8}+\frac{2}{8}+\frac{1}{8}\)) = \(\frac{21}{24}\)

x X \(\frac{9}{8}\)= \(\frac{21}{24}\)

x           = \(\frac{21}{24}\): \(\frac{9}{8}\)

x           = \(\frac{21}{24}\)X \(\frac{8}{9}\)

x           = \(\frac{7}{9}\)

\(x\times\frac{1}{2}+x\times\frac{1}{4}+x\times\frac{1}{8}=\frac{21}{24}\)

\(\Rightarrow x\times\left[\frac{1}{2}+\frac{1}{4}+\frac{1}{8}\right]=\frac{21}{24}\)

\(\Rightarrow x\times\left[\frac{4+2+1}{8}\right]=\frac{21}{24}\)

\(\Rightarrow x\times\frac{7}{8}=\frac{21}{24}\)

\(\Rightarrow x\times\frac{7}{8}=\frac{7}{8}\)

\(\Rightarrow x=\frac{7}{8}:\frac{7}{8}=1\)

a) \(x+4\frac{1}{5}=5\frac{2}{3}\times10\frac{1}{2}\)
    \(x+\frac{21}{5}=\frac{17}{3}\times\frac{21}{2}\)
    \(x+\frac{21}{5}=\frac{119}{2}\)
                   \(x=\frac{119}{2}-\frac{21}{5}\)
                   \(x=\frac{553}{10}\)
b) \(\frac{24}{5}-x=2\frac{1}{4}:1\frac{3}{4}\)
    \(\frac{24}{5}-x=\frac{9}{4}:\frac{7}{4}\)
    \(\frac{24}{5}-x=\frac{9}{4}.\frac{4}{7}\)
    \(\frac{24}{5}-x=\frac{9}{7}\)
                  \(x=\frac{24}{5}-\frac{9}{7}\)
                  \(x=\frac{123}{35}\)
 

x=291

x=21

x.84=252.97

x=24444:84

x=291

x.24=9.56

x=504:24

x=21

k nha

Theo đầu bài ta có:
\(\frac{x-7}{7}+\frac{x-7}{8}=\frac{15}{56}\)
\(\Rightarrow\left(x-7\right)\cdot\frac{1}{7}+\left(x-7\right)\cdot\frac{1}{8}=\frac{15}{56}\)
\(\Rightarrow\left(x-7\right)\cdot\left(\frac{1}{7}+\frac{1}{8}\right)=\frac{15}{56}\)
\(\Rightarrow\left(x-7\right)\cdot\frac{15}{56}=\frac{15}{56}\)
\(\Rightarrow x-7=1\)
\(\Rightarrow x=8\)

\(x.7+x.5-x-x.5=790\)

\(x.\left(7+5-1-5\right)=790\)

\(x.6=790\)

\(x=796:6\)

\(x=\frac{395}{3}\)

                 x X ( 7 + 5 - 1 - 5 ) = 790

                       x X 6 = 790

                      x = 790 : 6

 Vì ko có máy tính nên mk ko ghi kết quả cho bạn d

\(320\div x-10=5\cdot48\div24\)

\(320\div x-10=240\div24\)

\(320\div x-10=10\)

           \(320\div x=10+10\)

           \(320\div x=20\)

                        \(x=320\div20\)

                        \(x=16\)

\(320:x-10=5.48:24\)

\(320:x-10=240:24\)

\(320:x-10=10\)

\(320:x=10+10\)

\(320:x=20\)

\(x=320:20\)

\(x=16\)

1-[x(1/5+1)-2/3]=x-75

1-6/5x+2/3=x-75

1+2/3+75=x+6/5x

230/3=11/5x

x=230/3:11/5=1150/33

tui viet nham de bai ban oi

8,96 : X =2,03 -0,5

8,96 :X = 1,53

X = 8,96 -1,53

X = 7,43

1,2 .X = 0,54 - 0,06

1,2 .X = 0,48

X = 1,2 : 0,48

X = 2,5

\(\frac{17}{5}\)= 2\(\frac{7}{5}\); \(\frac{139}{12}\)= 10\(\frac{19}{12}\); \(\frac{150}{13}\)= 11\(\frac{7}{13}\)

NHỚ TK CHO MÌNH NHÉ

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