Question

CÁLCULOS PFV! 1-Determine o valor das expressões numéricas:

Answer 1

Resposta:

a)

$\sf\left ( -\dfrac{4}{5} \right ) \div \left ( +\dfrac{8}{5} \right ) - \left ( +2 \right )\times\left (- \dfrac{5}{2} \right )$

$\sf\left ( -\dfrac{4}{5} \right ) \times \left ( +\dfrac{5}{8} \right ) - \left ( +\dfrac{2}{1} \right )\times\left (- \dfrac{5}{2} \right )$

$\sf\left ( -\dfrac{20}{40} \right ) -\left (- \dfrac{10}{2} \right )$

$\sf \left ( -\dfrac{20\div 20}{40\div 20} \right ) + \dfrac{10}{2}$

$\sf -\dfrac{1}{2} + \dfrac{10}{2} =\sf \boxed{ \dfrac{9}{2}}$

b)

$\sf \left (- 1,44 \right ) \div \left -2,4 \right ) + \left ( + 0,18 \right ) \div \left ( - 1,2 \right ) =$

$\sf \left (+ 0,6 \right ) \right ) + \left ( - 0,15 \right ) =$

$\sf \left + 0,6) - 0,15 =$

$\sf \left + 0,6) - 0,15 =\\\sf \boxed{0,45}$

Explicação passo-a-passo: