Question

4)Efectuați,respectând semnificația parantezelor:
a)($\frac{1}{8}$+$\frac{1}{8}$×4)×($\frac{1}{2}$ - $\frac{2}{4}$)=
b)($\frac{15}{17}$+$\frac{123}{321}$ ÷ $\frac{41}{107}$ - $\frac{32}{17}$)×1999=
c)(3÷ $\frac{3}{2}$ - $\frac{3}{2}$ ÷3)×($\frac{1}{2}$+2)- $\frac{15}{4}$=
d)$\frac{8}{15}$ ÷ $\frac{4}{9}$×($\frac{1}{2}$+$\frac{1}{2}$ ÷2)  -$\frac{1}{15}$=
e)0,5×[$\frac{1}{3}$ -($\frac{1}{12}$+$\frac{3}{14}$+$\frac{1}{28}$)]=
f)($\frac{1}{3}$+$\frac{1}{3}$ ÷0,75)÷(- $\frac{1}{12}$)=
g)3$\frac{1}{2}$ ÷[- $\frac{1}{6}$+0.(3)-(0.25)]×0.5=
h)$\frac{14}{4}$+0.7×10÷(3+0.2×2$\frac{1}{2}$)=
                      Corectare
a)=0
b)=0
c)=0
d)=$\frac{5}{6}$
e)=0
f)= - $\frac{28}{3}$
g)=$\frac{35}{48}$
h)$\frac{11}{2}$

Answer 1

Trebuie sa respecti ordinea efectuarii operatiilor (efectuezi mai intai inmultirile si impartirile din paranteza,apoi restul operatiilor)
a) $( \frac{1}{8} + \frac{1}{4} ) * \frac{2-2}{4} = \frac{1+4}{8} * \frac{0}{4} Deoarece \frac{0}{4} =0 -> ecuatia va avea rezultatul 0$ (orice numar inmultit cu 0 da 0) 
b)$( \frac{15}{17}+ \frac{123}{321} * \frac{107}{41} - \frac{32}{17} ) * 1999 = ( \frac{15}{17} + \frac{3}{3} - \frac{32}{17} )*1999= \frac{15+17-32}{17} *1999=$0*1999=0

Sper ca ai inteles si ca o sa te descurci sa rezolvi restul exercitiilor. Succes!