giống bài mình cần mà ko có ai trả lời nhỉ

mong mọi người vô giúp 2 đứa mình với

B=81.(12.(1-1/7-1/289-1/85)/4.(1-1/7-1/289-1/85:5.(1+1/13+1/169+1/91)/6.(1+1/13+1/169+1/91).158158158/711711711

  =81.(12/4:5/6).158.1001001/711.1001001

=81.18/5.158/711

=324/5

\(B=81.\left[\frac{3\left(12-\frac{4}{7}-\frac{4}{289}-\frac{4}{85}\right)}{4-\frac{4}{7}-\frac{4}{289}-\frac{4}{85}}:\frac{5\left(1+\frac{1}{13}+\frac{1}{169}+\frac{1}{91}\right)}{6\left(1+\frac{1}{13}+\frac{1}{169}+\frac{1}{91}\right)}\right].\frac{79.2.1001001}{79.9.1001001}\)

\(B=81.\left[3.\frac{6}{5}\right].\frac{2}{9}\)

\(B=\frac{9.9.3.6.2}{5.9}\)

\(B=\frac{9.3.6.2}{5}\)

\(B=\frac{324}{5}\)

Tick cho minh nha Quang Hai Duong tick minh may man ca nam

Kakashi_kun linh tinh vừa thôi

Bài thế kia mà bảo là toán lớp 6

bạn ơi

P/s : nhìn thì khủng thật ! :v

\(B=81.\left[\frac{\left[12-\frac{12}{7}-\frac{12}{289}-\frac{12}{85}\right]}{4-\frac{4}{7}-\frac{4}{289}-\frac{4}{85}}:\frac{5+\frac{5}{13}+\frac{5}{169}+\frac{5}{91}}{6+\frac{6}{13}+\frac{6}{169}+\frac{6}{91}}\right].\frac{158158158}{711711711}\)

\(B=81.\left[\frac{12.\left(1-\frac{1}{7}-\frac{1}{289}-\frac{1}{85}\right)}{4.\left(1-\frac{1}{7}-\frac{1}{289}-\frac{1}{85}\right)}:\frac{5.\left(1+\frac{1}{13}+\frac{1}{169}+\frac{1}{91}\right)}{6.\left(1+\frac{1}{13}+\frac{1}{169}+\frac{1}{91}\right)}\right].\frac{158}{711}\)

\(B=81.\left(\frac{3}{1}:\frac{5}{6}\right).\frac{158}{711}\)

\(B=81.\frac{18}{5}.\frac{158}{711}\)

\(B=\frac{1458}{5}.\frac{158}{711}=\frac{324}{5}\)

Vậy  \(B=\frac{324}{5}\)

Cậu tính từng bước là ra thui

\(B=81.\left(\frac{12-\frac{12}{7}-\frac{12}{7}-\frac{12}{289}-\frac{12}{85}}{4-\frac{4}{7}-\frac{4}{289}-\frac{4}{85}}:\frac{5+\frac{5}{13}+\frac{5}{169}+\frac{5}{91}}{6+\frac{6}{13}+\frac{6}{169}+\frac{6}{91}}\right).\frac{158158158}{711711711}\)

\(\Leftrightarrow B=81.\left(\frac{12\left(1-\frac{1}{7}-\frac{1}{289}-\frac{1}{85}\right)}{4\left(1-\frac{1}{7}-\frac{1}{289}-\frac{1}{85}\right)}:\frac{5\left(1+\frac{1}{13}+\frac{1}{169}+\frac{1}{91}\right)}{6\left(1+\frac{1}{13}+\frac{1}{169}+\frac{1}{91}\right)}\right).\frac{158\left(1001001\right)}{711\left(1001001\right)}\)

\(\Leftrightarrow B=81\left(\frac{12}{3}:\frac{5}{6}\right).\frac{158}{711}\)

\(\Leftrightarrow B=81\left(3.\frac{6}{5}\right).\frac{2}{9}\)

\(\Leftrightarrow B=81.\frac{18}{5}.\frac{2}{9}\)

\(\Leftrightarrow B=\frac{324}{5}\)

Hok tốt!!

@ღTĭểυ Tɦưღ

Bước 3 của cậu sai rồi nha !!

\(=81.\dfrac{12.\left(1-\dfrac{1}{7}-\dfrac{1}{289}-\dfrac{1}{85}\right)}{4.\left(1-\dfrac{1}{7}-\dfrac{1}{289}-\dfrac{1}{85}\right)}:\dfrac{5.\left(1+\dfrac{1}{13}+\dfrac{1}{169}+\dfrac{1}{91}\right)}{6.\left(1+\dfrac{1}{13}+\dfrac{1}{169}+\dfrac{1}{91}\right)}.\dfrac{158}{711}\)

\(=81.\dfrac{12}{4}:\dfrac{5}{6}.\dfrac{2}{9}\)

\(=243:\dfrac{5}{6}.\dfrac{2}{9}\)

\(=\dfrac{1458}{5}.\dfrac{2}{9}\)

\(=\dfrac{324}{5}\)