Question

Calculați 3pe7 + 2 pe 15-8pe 35 +1pe 14

Answer 1

$\frac{3}{7} + \frac{2}{15} - \frac{8}{35} + \frac{1}{14} =$
$\frac{30 \times 3 + 14 \times 2 - 6 \times 8 + 15}{210} \\ = \frac{90 + 28 - 48 + 15}{210}= \frac{85}{210} \div 5 =$
$= \frac{17}{42}$