1.
\(\frac{5}{3}-\frac{1}{4}+\frac{1}{3}-\frac{3}{4}\)
\(=\left(\frac{5}{3}+\frac{1}{3}\right)-\left(\frac{1}{4}+\frac{3}{4}\right)\)
\(=2-1=1\)
\(\frac{2}{7}\cdot\frac{1}{5}+\frac{2}{7}\cdot\frac{4}{5}=\frac{2}{7}\cdot\left(\frac{1}{5}+\frac{4}{5}\right)=\frac{2}{7}\cdot1=\frac{2}{7}\)
#Louis
\(1.a)\frac{5}{3}-\frac{1}{4}+\frac{1}{3}-\frac{3}{4}\)
\(=\left(\frac{5}{3}+\frac{1}{3}\right)-\left(\frac{1}{4}+\frac{3}{4}\right)\)
\(=2-1\)
\(=1\)
\(b)\frac{2}{7}\times\frac{1}{5}+\frac{2}{7}\times\frac{4}{5}\)
\(=\frac{2}{7}\times\left(\frac{1}{5}+\frac{4}{5}\right)\)
\(=\frac{2}{7}\times1\)
\(=\frac{2}{7}\)
\(2.a)\frac{5}{6}+\frac{7}{12}-\frac{2}{9}\)
\(=\frac{30}{36}+\frac{21}{36}-\frac{8}{36}\)
\(=\frac{43}{36}\)
\(b)\frac{4}{9}\times\frac{5}{8}+\frac{1}{6}\)
\(=\frac{5}{18}+\frac{1}{6}=\frac{5}{18}+\frac{3}{18}\)
\(=\frac{8}{18}=\frac{4}{9}\)
\(c)2:\frac{3}{11}-\frac{13}{12}\)
\(=2\times\frac{11}{3}-\frac{13}{12}\)
\(=\frac{22}{3}-\frac{13}{12}\)
\(=\frac{25}{4}\)
\(\frac{5}{3}-\frac{1}{4}+\frac{1}{3}-\frac{3}{4}\)
\(=\left(\frac{5}{3}-\frac{1}{3}\right)+\left(\frac{1}{4}-\frac{3}{4}\right)\)
\(=\frac{4}{3}+-\frac{2}{4}\)
\(=\frac{16}{12}+-\frac{6}{12}\)
\(=\frac{10}{12}=\frac{5}{6}\)
\(\frac{2}{7}\times\frac{1}{5}+\frac{2}{7}\times\frac{4}{5}\)
\(=\frac{2}{7}\times\left(\frac{1}{5}+\frac{4}{5}\right)\)
\(=\frac{2}{7}\times\frac{5}{5}\)
\(=\frac{2}{7}\times1\)
\(=\frac{2}{7}\)
\(\frac{5}{6}+\frac{7}{12}-\frac{2}{9}\)
\(=\frac{30}{36}+\frac{21}{36}-\frac{8}{36}\)
\(=\frac{30+21-8}{36}\)
\(=\frac{43}{36}\)
\(\frac{4}{9}\times\frac{5}{8}+\frac{1}{6}\)
\(=\frac{2}{9}\times\frac{5}{4}+\frac{1}{6}\)
\(=\frac{10}{36}+\frac{1}{6}\)
\(=\frac{10}{36}+\frac{6}{36}\)
\(=\frac{16}{36}=\frac{8}{18}=\frac{4}{9}\)
1)a) 5/3-1/4+1/3-3/4
= (5/3+1/3)-(1/4+3/4)
=2-1=1
b) 2/7 x 1/5 + 2/7 x 4/5
=2/7 x (1/5 + 4/5)
=2/7 x 1=2/7
