\(\frac{3}{5}.\frac{13}{46}-\frac{1}{10}.\frac{16}{23}\)

\(=\frac{3}{5}.\left(\frac{1}{46}.13\right)-\frac{1}{10}.\frac{32}{46}\)

\(=\left(\frac{3}{5}.13\right).\frac{1}{46}-\left(\frac{1}{10}.32\right).\frac{1}{46}\)

\(=\frac{39}{5}.\frac{1}{46}-\frac{32}{10}.\frac{1}{46}\)

\(=\frac{78}{10}.\frac{1}{46}-\frac{32}{10}.\frac{1}{46}\)

\(=\left(\frac{78}{10}-\frac{32}{10}\right).\frac{1}{46}\)

\(=\frac{46}{10}.\frac{1}{46}\)

\(=\frac{1}{10}\)

q - 4 /6  =   5 /9

         q   = 5/9 + 4/6

          q = 11/9

\(q-\frac{4}{6}=\frac{5}{9}\)

\(q=\frac{5}{9}+\frac{4}{6}\)

\(q=\frac{11}{9}\)

\(\frac{1}{7}.\frac{-3}{8}+\frac{1}{7}.\frac{-13}{8}\)

\(=\frac{1}{7}\left(\frac{-3}{8}+\frac{-13}{8}\right)\)

\(=\frac{1}{7}.-2\)

\(=\frac{-2}{7}\)

\(\frac{1}{7}.\frac{-3}{8}+\frac{1}{7}.\frac{-13}{8}\)

\(=\frac{1}{7}\left(\frac{-3}{8}+\frac{-13}{8}\right)\)

\(=\frac{1}{7}.\left(-2\right)\)

\(=\frac{-2}{7}\)

\(\text{Phần a nên sửa đề thế này :}\) \(\frac{1}{7}.\frac{-3}{8}+\frac{1}{7}.\frac{-13}{8}\)

\(\text{Giải :}\)

\(\frac{1}{7}.\frac{-3}{8}+\frac{1}{7}.\frac{-13}{8}\)

\(=\frac{1}{7}\left(\frac{-3}{8}+\frac{-13}{8}\right)\)

\(=\frac{1}{7}.\left(-2\right)\)

\(=\frac{-2}{7}\)

\(\frac{3}{5}.\frac{13}{46}-\frac{1}{10}.\frac{16}{23}\)

\(=\frac{3}{5}.\left(\frac{1}{46}.13\right)-\frac{1}{10}.\frac{32}{46}\)

\(=\left(\frac{3}{5}.13\right).\frac{1}{46}-\left(\frac{1}{10}.32\right).\frac{1}{46}\)

\(=\frac{39}{5}.\frac{1}{46}-\frac{32}{10}.\frac{1}{46}\)

\(=\frac{78}{10}.\frac{1}{46}-\frac{32}{10}.\frac{1}{46}\)

\(=\left(\frac{78}{10}-\frac{32}{10}\right).\frac{1}{46}\)

\(=\frac{46}{10}.\frac{1}{46}\)

\(=\frac{1}{10}\)

\(y:0,001+y:0,01+y:0,1=99:\frac{1}{100}\)

\(\Rightarrow y\times1000+y\times100+y\times10=99\times100\)

\(\Rightarrow y\times\left(1000+100+10\right)=9900\)

\(\Rightarrow y\times1110=9900\)

\(\Rightarrow y=\frac{9900}{1110}\)

y x 1000+ y x 100+ y x 10 = 99x100

y x( 1000+100+10)            = 9900

y x 1110                             = 9900

y                                         = 9900: 1110

y                                         =  \(\frac{9900}{1110}=\frac{330}{37}\)

     HT

\(\frac{7}{15}.\left(\frac{-3}{8}-\frac{3}{7}\right)\)

\(=\frac{7}{15}.\frac{-3}{8}-\frac{7}{15}.\frac{3}{7}\)

\(=\frac{-7}{40}-\frac{1}{5}\)

\(=\frac{-7}{40}-\frac{8}{40}\)

\(=\frac{-3}{8}\)

Trả lời:
\(\frac{7}{15}.\left(\frac{-3}{8}-\frac{3}{7}\right)=\frac{7}{15}.\left(\frac{-21}{56}-\frac{24}{56}\right)=\frac{7}{15}.\frac{-45}{56}\)\(=\frac{-315}{840}=\frac{3}{8}\)

Chúc bn học tốt

\(\frac{1}{6}.\frac{9}{-8}.\frac{-12}{11}\)

\(=\left(\frac{1}{6}.\frac{-12}{11}\right).\frac{9}{-8}\)

\(=\frac{-2}{11}.\frac{9}{-8}\)

\(=\frac{9}{44}\)

\(\left(\frac{17}{18}:\frac{51}{36}\right).\frac{3}{5}\)

\(=\left(\frac{17}{18}.\frac{36}{51}\right).\frac{3}{5}\)

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

\(=\frac{2}{5}\)

a) 2004 - 5 x 100

   = 2004 - 500

   = 1504

 b) 1850 + 4 - 4 x 50

   = 1850 + 4 - 200

   = 1854 - 200

   = 1654 

                          ~HỌC TỐT~

Ô tô đi với v=850m/p

850m=0,85km

1p=\(\frac{1}{60}h\)

Vậy ô tô đi với v=\(0,85:\frac{1}{60}=51\)(km/h)

Vậy:......

#H

1. x mu3-2xmu2+2a-9 nha

lam123 ko đăng linh tinh mik sẽ tạng bạn 1 vé báo cáo