354

a: \(\left(\frac{11}{4}-\frac78\right):\frac{11}{2}\)

\(=\left(\frac{22}{8}-\frac78\right)\times\frac{2}{11}\)

\(=\frac{15}{8}\times\frac{2}{11}=\frac{15}{4\times11}=\frac{15}{44}\)

b: Sửa đề: \(\frac{29}{44}:\frac{15}{44}\times\frac{15}{88}:\frac{165}{16}\)

\(=\frac{29}{44}\times\frac{44}{15}\times\frac{15}{88}\times\frac{16}{165}\)

\(=\frac{29}{88}\times\frac{16}{165}=29\times\frac{2}{11\times165}=\frac{58}{1815}\)

=(2+8)+(3+7)+(4+6)+5

=10+10+10+5

=30+5

=35

2 + 3 + 4 + 5 + 6 + 7 + 8

= (2 + 8) + (3 + 7) + (4 + 6) + 5

= 10 + 10 + 10 + 5

= 10 x 3 + 5

= 30 + 5

= 35

71 804;2 678 418;

=2 bạn nhé. nhớ cho mình

chúc bạn học tốt

đáp án là 2 k mình đúng đi

\(\frac{8}{5}-\frac{18}{27}\)

\(=\frac{8}{5}-\frac{2}{3}\)

\(=\frac{24}{15}-\frac{10}{15}\)

\(=\frac{14}{15}\)

\(\frac{12}{20}-\frac{6}{18}\)

\(=\frac{3}{5}-\frac{1}{3}\)

\(=\frac{9}{15}-\frac{5}{15}\)

\(=\frac{4}{15}\)

\(\frac{8}{24}-\frac{5}{25}\)

\(=\frac{1}{3}-\frac{1}{5}\)

\(=\frac{5}{15}-\frac{3}{15}\)

\(=\frac{2}{15}\)

\(\frac{18}{21}-\frac{12}{27}\)

\(=\frac{6}{7}-\frac{4}{9}\)

\(=\frac{54}{63}-\frac{28}{63}\)

\(=\frac{26}{63}\)

1)8/5-2/3=14/15

2)3/5-1/3=4/15

3)1/3-1/5=2/15

4)6/7-4/9=26/63

\(a,\frac{8}{15}+\frac{2}{3}=\frac{8+10}{15}=\frac{18}{15}=\frac{6}{5}\)

\(b,\frac{3}{7}+\frac{4}{8}=\frac{24+28}{56}=\frac{62}{56}=\frac{31}{28}\)

a) \(\frac{8}{15}+\frac{2}{3}=\frac{8}{15}+\frac{10}{15}=\frac{8+10}{15}=\frac{18}{15}=\frac{6}{5}\)

b) \(\frac{3}{7}+\frac{4}{8}=\frac{24}{56}+\frac{28}{56}=\frac{24+28}{56}=\frac{52}{56}=\frac{13}{14}\)

109 nha

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que diem o giua so 8 

di chuyển que diêm ở giữa số 8