Question

b) 3/2+2/7
c) - 3/2+ 2- 2/3 × 5/2
d) 2/3 × 4/5
e) - 2/3 + 1 - 3/2 × 8/9​

Answer 1

Resposta:

$b) \frac{3}{2} + \frac{2}{7} \\ \frac{21}{14} + \frac{4}{14} \\ \frac{21 + 4}{14} = \frac{25}{14}$

$c) - \frac{3}{2} + 2 - \frac{2}{3} \times \frac{5}{2} \\ - \frac{3}{2} + \frac{4}{2} - \frac{2}{3} \times ( \frac{5}{2} ) \\ \frac{ - 3 + 4}{2} - \frac{2}{3} \times \frac{5}{2} ) \\ \frac{1}{2} - \frac{2}{3} \times ( \frac{5}{2} ) \\ \frac{1}{2} - \frac{2 \times 5}{3 \times 2} \\ \frac{1}{2} - \frac{5}{3} \\ \frac{3}{6} - \frac{10}{6} \\ \frac{3 - 10}{6} \\ = - \frac{7}{6}$

$d) \frac{2}{3} \times \frac{4}{5} \\ \frac{2 \times 4}{3 \times 5} = \frac{8}{15}$

$e) - \frac{2}{3} + 1 - \frac{3}{2} \times \frac{8}{9} \\ - \frac{2}{3} + \frac{3}{3} - \frac{3}{2} \times \frac{8}{9} \\ \frac{ - 2 + 3}{3} - \frac{3}{2} \times ( \frac{8}{9} ) \\ \frac{1}{3} - \frac{3}{2} \times ( \frac{8}{9} ) \\ \frac{1}{3} - \frac{3 \times 8}{2 \times 9} \\ \frac{1}{3} - \frac{24}{18} \\ \frac{1}{3} - \frac{4}{3} \\ \frac{ 1 - 4}{3} \\ \frac{ - 3}{3} \\ = - 1$