Question

Calculați pe lung ex 3

Answer 1

a) $\\\frac{4}{5} .1\frac{1}{4} .\frac{2}{3} =\\\\\frac{4}{5} .\frac{5}{4} .\frac{2}{y3} =\\\\\frac{1}{5} .5.\frac{2}{3}=\\\\\frac{2}{3}$

b)  $4\frac{1}{3} .(1\frac{2}{3} .\frac{3}{5} )\\\\4\frac{1}{4} .(\frac{5}{3} .\frac{3}{5} )\\\\4\frac{1}{3} .(\frac{1}{3} .3)\\\\4\frac{3}{1} .1\\\\4\frac{1}{3}$

c)  $2\frac{3}{7} .\frac{7}{17} .1\frac{1}{8} \\\\\frac{17}{7} .\frac{7}{17} .1\frac{1}{8} \\\\\frac{17}{7} .\frac{7}{17}.\frac{9}{8} \\\\\frac{1}{7} .\frac{7}{1} .\frac{9}{8} \\\\\frac{9}{8}$

Sper ca team ajutat

Answer 2

$\displaystyle a)~\frac{4}{5} \cdot 1\frac{1}{4} \cdot \frac{2}{3} =\frac{4}{5} \cdot \frac{1\cdot 4+1}{4} \cdot \frac{2}{3} =\frac{4}{5} \cdot \frac{4+1}{4} \cdot \frac{2}{3} =\frac{\not4_1}{\not5_1} \cdot \frac{\not5_1}{\not4_1} \cdot \frac{2}{3} =1 \cdot \frac{2}{3} =\frac{2}{3}$

$\displaystyle b)~4\frac{1}{3} \cdot \Bigg(1\frac{2}{3} \cdot \frac{3}{5} \Bigg)=\frac{4\cdot 3+1}{3} \cdot \Bigg(\frac{1\cdot 3+2}{3} \cdot \frac{3}{5} \Bigg)=\frac{12+1}{3} \cdot\Bigg(\frac{3+2}{3} \cdot \frac{3}{5} \Bigg)=\\\\=\frac{13}{3} \cdot \Bigg(\frac{\not5_1}{\not3_1} \cdot \frac{\not3_1}{\not5_1} \Bigg)=\frac{13}{3} \cdot 1=\frac{13}{3}$

$\displaystyle c)~2\frac{3}{7} \cdot \frac{7}{17} \cdot 1\frac{1}{8} =\frac{2\cdot 7+3}{7} \cdot \frac{7}{17} \cdot \frac{1\cdot8+1}{8} =\frac{14+3}{7} \cdot \frac{7}{17} \cdot \frac{8+1}{8} =\\\\=\frac{_1\not17}{\not7_1} \cdot \frac{\not7_1}{_1\not17} \cdot \frac{9}{8} =1 \cdot \frac{9}{8} =\frac{9}{8}$