45/12+3/6=51/12

\(\frac{45}{12}+\frac{3}{6}=\frac{51}{12}\)

\(\frac{45}{12}+\frac{3}{6}=\frac{15}{4}+\frac{1}{2}=\frac{15}{4}+\frac{2}{4}=\frac{15+2}{4}=\frac{17}{4}\)

\(2\frac{4}{3}+\frac{4}{12}=\frac{2.3+4}{3}+\frac{4}{12}=\frac{10}{3}+\frac{4}{12}=\frac{40}{12}+\frac{4}{12}=\frac{44}{12}=\frac{11}{3}\)

\(2\frac{4}{3}=\frac{10}{3}\)

\(\frac{10}{3}+\frac{4}{12}=\frac{120}{36}+\frac{12}{36}\)

\(=\frac{132}{36}=\frac{22}{6}=\frac{11}{3}\)

\(\frac{3}{12}+\frac{2}{4}-\frac{2}{12}\)

\(=\frac{3}{12}+\frac{6}{12}-\frac{2}{12}\)

\(=\frac{3+6-2}{12}\)

\(=\frac{7}{12}\)

\(\frac{3}{12}+\frac{2}{4}-\frac{2}{12}\)

\(=\frac{3}{12}+\frac{6}{12}-\frac{2}{12}\)

\(=\frac{9}{12}-\frac{2}{12}\)

\(=\frac{7}{12}\)

\(\frac{3}{12}+\frac{2}{4}-\frac{2}{12}\)

\(=\frac{3}{12}+\frac{6}{12}-\frac{2}{12}\)

\(=\frac{7}{12}\)

\(-\frac{3}{4}=-\frac{15}{20}\)

\(\frac{4}{-5}=-\frac{16}{20}\)

Do \(-15>-16\)

\(\Rightarrow-\frac{3}{4}>\frac{4}{-5}\)

So sánh \(\frac{-3}{4}........\frac{4}{-5}\) hay \(\frac{-3}{4}.......\frac{-4}{5}\)

Ta có :

\(1+\frac{-3}{4}=\frac{1}{4}\)

\(1+\frac{-4}{5}=\frac{1}{5}\)

Vì \(\frac{1}{4}>\frac{1}{5}\Rightarrow1+\frac{-3}{4}>1+\frac{-4}{5}\Rightarrow\frac{-3}{4}>\frac{-4}{5}\)

\(\Rightarrow\frac{-3}{4}>\frac{4}{-5}\)

Vậy \(\frac{-3}{4}>\frac{4}{5}\)

\(2\frac{1}{2}:\frac{3}{4}=\frac{5}{2}:\frac{3}{4}\)

= 5/2 x 4/3

=\(\frac{20}{6}\)

M.n tk giùm em vs ạ !! ^_^

=1/2+2+5/3=25/6 tk mk nha mình  là bạn cậu nè

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

k cho mk vs nhé

k cho mk vs nhé

mình nè

= 2x4/3x4 + 3x3/4x3 +3/12=8/12+9/12+3/12=8+9+3/12=20/12=5/3

dễ sợ thiệt

Mấy bạn dùng mấy cái này để xin đúng

\(12\frac{4}{5}\)=\(\frac{64}{5}\).

Ta có :

\(\frac{64}{5}+\frac{4}{5}=\frac{68}{5}\)

\(12\frac{4}{5}+\frac{4}{5}=\frac{64}{5}+\frac{4}{5}=\frac{68}{5}\)

\(12\frac{4}{5}+\frac{4}{5}=\frac{12x5+4}{5}+\frac{4}{5}=\frac{64}{5}+\frac{4}{5}=\frac{68}{5}\)

1/3+1/4+4/5-1/2=4/12+3/12+4/5-1/2=7/12+4/5-1/2=35/60+48/60-1/2=83/60-1/2=83/60-30/60

=53/60

MTC;60

20/60+15/60+12/60-30/60

=20+15+12-30

=17    nha bn

MẪU SỐ CHUNG NHỎ NHẤT LÀ 60

\(\frac{20}{60}+\frac{15}{60}+\frac{12}{60}-\frac{30}{60}=\frac{20+15+12-30}{60}=\frac{17}{60}\)