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trả lời cẩn thận đi minato

thế các bạn có trả lời đàng hoàng giùm mình ko

bạn bị lỗi rồi

\(12:\left\{400:\left[500-\left(5^3+5^2\cdot7\right)\right]\right\}\)

\(=12:\left\{400:200\right\}\)

=12:2

=6

\(=\dfrac{7-2}{2.7}+\dfrac{12-7}{7.12}+...+\dfrac{102-97}{97.102}\)

\(=\dfrac{1}{2}-\dfrac{1}{7}+\dfrac{1}{7}-\dfrac{1}{12}+...+\dfrac{1}{97}-\dfrac{1}{102}\)

\(=\dfrac{1}{2}-\dfrac{1}{102}=\dfrac{25}{51}\)

\(=\dfrac{7-2}{2.7}+\dfrac{12-7}{7.12}+...+\dfrac{97-92}{92.97}\)

\(=\dfrac{1}{2}-\dfrac{1}{7}+\dfrac{1}{7}-\dfrac{1}{12}+...+\dfrac{1}{92}-\dfrac{1}{97}\)

\(=\dfrac{1}{2}-\dfrac{1}{97}=\dfrac{95}{194}\)

Mình xin được sửa lại vì câu đầu mình nhầm đề bài ạ

\(=5+\dfrac{4}{5}\left(\dfrac{5}{2\cdot7}+\dfrac{5}{7\cdot12}+...+\dfrac{5}{52\cdot57}\right)\)

\(=5+\dfrac{4}{5}\left(\dfrac{1}{2}-\dfrac{1}{7}+\dfrac{1}{7}-\dfrac{1}{12}+...+\dfrac{1}{52}-\dfrac{1}{57}\right)\)

\(=5+\dfrac{4}{5}\cdot\dfrac{55}{114}=\dfrac{307}{57}\)

a, 3/5 x 7/9 + 11/9 x 3/5 = 3/5 x (7/9 + 11/9) = 3/5 x 2 = 6/5

b, 14/13 : 1/2 + 3/13 x 2 - 2 x 7/13

= 14/13 x 2 + 3/13 x 2 - 2 x 7/13

= 2 x ( 14/13 + 3/13 - 7/13)

= 2 x 10/13 = 20/13

\(\left(\frac{13}{84}.\frac{7}{5}-\frac{5}{2}.\frac{7}{180}\right):\frac{43}{18}+\frac{9}{2}.\frac{1}{10}\)

\(=\frac{43}{360}:\frac{43}{18}+\frac{9}{20}=\frac{1}{20}+\frac{9}{20}=\frac{10}{20}=\frac{1}{2}\)

9 x0+1+1+1+1:2x7

=0+4:2x7

=4:2x7

=2x7

=14

6,5 nhá :D

9 x 0 + 1 + 1 + 1 + 1 : 2 x 7

= 6,5

k mình nha bạn