Bài làm

\(\frac{1313}{1010}+x=\frac{1414}{2828}\)

\(\Rightarrow\frac{13}{10}+x=\frac{14}{28}\)

\(x=\frac{14}{28}-\frac{13}{10}\)

\(x=\frac{1}{2}-\frac{13}{10}\)

\(x=\frac{10}{20}-\frac{26}{20}\)

\(x=-\frac{16}{20}\)

\(x=-\frac{4}{5}\)

Vậy \(x=-\frac{4}{5}\)

\(\frac{1010+1111+1212+1313+1414+1515}{2020+2121+2222+2323+2424+2525}=\frac{10\times101+11\times101+12\times101+13\times101+14\times101+15\times101}{20\times101+21\times101+22\times101+23\times101+24\times101+25\times101}=\frac{101\times\left(10+11+12+13+14+15\right)}{101\times\left(20+21+22+23+24+25\right)}\)

\(=\frac{10+11+12+13+14+15}{20+21+22+23+24+25}=\frac{75}{135}=\frac{5}{9}\)

1010+1111+1212+1313+1414+1515= 7575

2020+2121+2222+2323+2424+2525= 13635

có 1 dấu gạch ngang mờ nhạt kìa bạn

mình trả lời bạn k mình nhé

ok bạn

a)\(\Leftrightarrow\)\(x=\dfrac{2323}{4646}-\dfrac{1313}{2828}\)

\(\Leftrightarrow\)\(x=\dfrac{1}{28}\)

b)\(\Leftrightarrow\)\(x=\dfrac{23}{69}-\dfrac{17}{153}\)

\(\Leftrightarrow\)\(x=\dfrac{2}{9}\)

a) \(\dfrac{1313}{2828}\) + \(x\) = \(\dfrac{2323}{4646}\)

\(\dfrac{13}{28}\) + \(x\) = \(\dfrac{1}{2}\)

\(x=\dfrac{1}{2}-\dfrac{13}{28}\)

\(x=\dfrac{14}{28}-\dfrac{13}{28}\)

\(x=\dfrac{1}{28}\)

b) \(\dfrac{23}{69}-x=\dfrac{17}{153}\)

\(\dfrac{1}{3}-x=\dfrac{1}{9}\)

\(x=\dfrac{1}{9}+\dfrac{1}{3}\)

\(x=\dfrac{1}{9}+\dfrac{3}{9}\)

\(x=\dfrac{4}{9}\)

\(\frac{1313}{2828}+x=\frac{2323}{4646}\)

hay \(\frac{13}{28}+x=\frac{1}{2}\)

\(x=\frac{1}{2}-\frac{13}{28}\)

\(x=\frac{1}{28}\)

\(\frac{23}{69}-x=\frac{17}{153}\)

hay \(\frac{1}{3}-x=\frac{1}{9}\)

\(x=\frac{1}{3}-\frac{1}{9}\)

\(x=\frac{2}{9}\)

a) \(\dfrac{10}{20}=\dfrac{10:10}{20:10}=\dfrac{1}{2}\)

\(\dfrac{12}{72}=\dfrac{12:12}{72:12}=\dfrac{1}{6}\)

\(\dfrac{14}{42}=\dfrac{14:14}{42:14}=\dfrac{1}{3}\)

\(\dfrac{25}{100}=\dfrac{25:25}{100:25}=\dfrac{1}{4}\)

b) \(\dfrac{1010}{1313}=\dfrac{1010:101}{1313:101}=\dfrac{10}{13}\)

\(\dfrac{1111}{1414}=\dfrac{1111:101}{1414:101}=\dfrac{11}{14}\)

c) \(\dfrac{143}{154}=\dfrac{143:11}{154:11}=\dfrac{13}{14}\)

\(\dfrac{990}{2610}=\dfrac{990:90}{2610:90}=\dfrac{11}{29}\)

\(\dfrac{374}{506}=\dfrac{374:22}{506:22}=\dfrac{17}{23}\)

\(a)\dfrac{10}{20}=\dfrac{1}{2};\dfrac{12}{72}=\dfrac{1}{6};\dfrac{14}{42}=\dfrac{1}{3};\dfrac{25}{100}=\dfrac{1}{4}\)

\(b)\dfrac{1010}{1313}=\dfrac{10}{13};\dfrac{1111}{1414}=\dfrac{11}{14}\)

\(c)\dfrac{143}{154}=\dfrac{13}{14};\dfrac{990}{2610}=\dfrac{11}{29};\dfrac{374}{506}=\dfrac{17}{23}\)

Chúc bn học tốt !!!

giup mk voi

\(a,\frac{1313}{2828}+x=\frac{2323}{4646}\)

\(\frac{13}{28}+x=\frac{1}{2}\)

\(x=\frac{1}{2}-\frac{13}{28}=\frac{1}{28}\)

\(b,\frac{5}{7}+\frac{x}{35}=\frac{4}{5}\)

\(\frac{x}{35}=\frac{4}{5}-\frac{5}{7}=\frac{3}{35}\)

\(\Rightarrow x=3\)

\(c,\frac{23}{69}-x=\frac{17}{153}\)

\(\frac{1}{3}-x=\frac{1}{9}\)

\(x=\frac{1}{3}-\frac{1}{9}=\frac{2}{9}\)

\(a,\frac{1313}{2828}+x=\frac{2323}{4646}\)

\(\frac{13}{28}+x=\frac{1}{2}\)

\(x=\frac{1}{2}-\frac{13}{28}=\frac{1}{28}\)

\(b,\frac{5}{7}+\frac{x}{35}=\frac{4}{5}\)

\(\frac{x}{35}=\frac{4}{5}-\frac{5}{7}=\frac{3}{35}\)

\(\Rightarrow x=3\)

\(c,\frac{23}{69}-x=\frac{17}{153}\)

\(x=\frac{23}{69}-\frac{17}{153}=\frac{2}{9}\)

Lúc nãy, cô còn dạy học nên giờ cô mới giảng cho em được nhé.

B = (1 - \(\dfrac{1}{2}\))\(\times\)(1 - \(\dfrac{1}{3}\))\(\times\)(1 - \(\dfrac{1}{4}\))\(\times\)(1-\(\dfrac{1}{5}\))\(\times\)...\(\times\)(1- \(\dfrac{1}{2003}\))\(\times\)(1-\(\dfrac{1}{2004}\))

B = \(\dfrac{2-1}{2}\)\(\times\)\(\dfrac{3-1}{3}\)\(\times\)\(\dfrac{4-1}{4}\)\(\times\)\(\dfrac{5-1}{5}\)\(\times\)...\(\times\)(\(\dfrac{2003-1}{2003}\))\(\times\)(\(\dfrac{2004-1}{2004}\))

B = \(\dfrac{1}{2}\)\(\times\)\(\dfrac{2}{3}\)\(\times\)\(\dfrac{3}{4}\)\(\times\)\(\dfrac{4}{5}\)\(\times\)...\(\times\)\(\dfrac{2002}{2003}\)\(\times\)\(\dfrac{2003}{2004}\)

B = \(\dfrac{2\times3\times4\times...\times2003}{2\times3\times4\times...\times2003}\)\(\times\) \(\dfrac{1}{2004}\)

B = \(\dfrac{1}{2004}\)