Mk ko ghi lại đề nhé

1 = \(350-4.19+4.7\)

\(=350-4.\left(19+7\right)\)

\(=350+4.26\)

\(=350-104=246\)

2 Câu này mình vẫn chưa hiểu là bạn ghi 27  3/5 tức là 27.3/5 hay 27\(\dfrac{3}{5}\)nên mk bỏ qua nhé

3 Cái đoạn 1 1/3 y chang câu 2 

4 \(=\dfrac{2}{3}+\dfrac{1}{3}.\dfrac{7}{18}.\dfrac{12}{7}\)

\(=\dfrac{2}{3}+\dfrac{7}{54}.\dfrac{12}{7}\)

\(=\dfrac{2}{3}+\dfrac{2}{9}=\dfrac{8}{9}\)

5 \(=2^2+10^2-\left[9.\left(112:8\right)-11\right].1\)

\(=4+100-\left(9.14-11\right)\)

\(=104-115\)\(=-11\)

6 Đoạn 6 3/5 y chang 2,3

7 \(=\left(\dfrac{2}{3}-1\right)+\left(\dfrac{2}{7}-\dfrac{3}{7}\right)-\left(\dfrac{1}{14}-\dfrac{3}{28}\right)\)

\(=\dfrac{-1}{3}+\dfrac{-1}{7}-\dfrac{-1}{28}\)

\(=\dfrac{-196}{588}+\dfrac{-84}{588}-\dfrac{-21}{588}\)\(=\dfrac{259}{588}\)

Làm tạm tạm thôi xl vì có 3 câu ko hiểu 

\(a.=\dfrac{2019}{2020}\times\left(\dfrac{4}{11}+\dfrac{5}{11}+\dfrac{2}{11}\right)\\ =\dfrac{2019}{2020}\times1=\dfrac{2019}{2020}\\ b.=\dfrac{25}{27}\times\left(\dfrac{17}{14}-\dfrac{1}{14}-\dfrac{2}{14}\right)\\ =\dfrac{25}{27}\times1=\dfrac{25}{27}\)

Thanks mik chữ cũng hơi ẩu

\(\frac{5}{11}+\frac{1}{14}+\frac{2}{5}+\frac{6}{11}+\frac{3}{4}+\frac{6}{25}+\frac{9}{25}\)

\(=\frac{5}{11}+\frac{6}{11}+\frac{1}{14}+\frac{3}{4}+\frac{2}{5}+\frac{6}{25}+\frac{9}{25}\)

\(=1+\frac{23}{28}+1\)

\(=\frac{79}{28}\)

Bạn có thể xem ở đây : Tại đây

=1/14 +1/4+(2/5+6/25+9/25)+(6/11+5/11)

=4/64+16/64+1+1

=20/64+1+1

=5/16+1+1

=2 và 5/16

\(\frac{5}{11}+\frac{1}{14}+\frac{2}{5}+\frac{6}{11}+\frac{3}{4}+\frac{6}{25}+\frac{9}{25}\)

\(=\left(\frac{5}{11}+\frac{6}{11}\right)+\left(\frac{1}{14}+\frac{3}{4}\right)+\left(\frac{6}{25}+\frac{9}{25}\right)+\frac{2}{5}\)

\(=1+\frac{23}{28}+\frac{3}{5}+\frac{2}{5}\)

\(=1+\frac{23}{28}+1\)

\(=2+\frac{23}{28}\)

\(=\frac{79}{28}\)

Ai k mik mik k lại

\(\frac{79}{28}\)nha bạn

Cho mình sửa lại đề tí nhé bạn , nếu có gì sai liên hệ với mình !

\(\frac{5}{11}+\frac{1}{4}+\frac{2}{5}+\frac{6}{11}+\frac{3}{4}+\frac{6}{25}+\frac{9}{25}\)

\(=\frac{5}{11}+\frac{6}{11}+\frac{1}{4}+\frac{3}{4}+\frac{2}{5}+\frac{6}{25}+\frac{9}{25}\)

\(=1+1+1\)

\(=3\)

\(\frac{79}{28}\)nha bạn

386 cả 2 câu nha bạn

25*16-14=386

25*15+11=386

a/ 25*16 -14=386

b/ 25*15+11=386

    ĐS:a/386

         b/386

\(\dfrac{1}{3}+\dfrac{14}{25}-\dfrac{4}{3}+\dfrac{2}{7}+\dfrac{11}{25}\)= \(\left(\dfrac{1}{3}-\dfrac{4}{3}\right)+\left(\dfrac{14}{25}+\dfrac{11}{25}\right)+\dfrac{2}{7}=-1+1+\dfrac{2}{7}=\dfrac{2}{7}\)

\(=>A=\left(\dfrac{1}{3}-\dfrac{4}{3}\right)+\left(\dfrac{14}{25}+\dfrac{11}{25}\right)+\dfrac{2}{7}=-1+1+\dfrac{2}{7}=\dfrac{2}{7}\)

=2/7

\(\dfrac{5}{15}+\dfrac{14}{25}-\dfrac{4}{3}+\dfrac{11}{25}\\ =\left(\dfrac{5}{15}-\dfrac{4}{3}\right)+\left(\dfrac{14}{25}+\dfrac{11}{25}\right)\\ =\left(\dfrac{5}{15}-\dfrac{20}{15}\right)+\dfrac{25}{25}\\ =\dfrac{-15}{15}+\dfrac{25}{25}\\ =-1+1\\ =0\)

\(\dfrac{5}{15}\) +  \(\dfrac{14}{25}\) − \(\dfrac{4}{3}\) + \(\dfrac{11}{25}\)\(\dfrac{11}{25}\)

=   [ \(\dfrac{5}{15}\)− \(\dfrac{4}{3}\) ] + [ \(\dfrac{14}{25}\) + 

515+1425−43+1125=(515−43)+(1425+1125)=(515−2015)+2525=−1515+2525=−1+1=0

tất cả là 1

bằng1

mk bảo chuyển từ phân số sang mẫy số chứ ko phải như các cậu

các cậu biết hỗn số là gì không

ví dụ : 

\(=\dfrac{1}{5}+\dfrac{2}{5}+\dfrac{3}{5}=\dfrac{6}{5}\)

   \(\dfrac{11}{55}+\dfrac{14}{35}+\dfrac{15}{25}\)

\(=\dfrac{1}{5}+\dfrac{2}{5}+\dfrac{3}{5}\)

\(=\dfrac{1+2+3}{5}\)

\(=\dfrac{6}{5}\)

\(\dfrac{11}{55}+\dfrac{14}{35}+\dfrac{15}{25}=\dfrac{6}{5}\)