Question

Rapiiid!!!! Dau 12 puncte

Answer 1

Răspuns:

    a) $\frac{41}{108}$

    b) 2.155

    c) 1.58(3)

    d) 1.07

Explicație pas cu pas:

  a)   $m_{a}$ = ($\frac{1}{6} + \frac{2}{9} +\frac{3}{4}$) ÷ 3 (acum inmultim prima fractie cu 6, a doua cu 4 si a treia cu 9)

    $m_{a}$ = ($\frac{6}{36} + \frac{8}{36} + \frac{27}{36}$) ÷ 3

    $m_{a}$ = $\frac{41}{36}$ ÷ 3 =  $\frac{41}{36}$ × $\frac{1}{3}$ = $\frac{41}{108}$

 b) $m_{b}$ = ($\frac{3}{7} + \frac{1}{5} + 2 + 6$) ÷ 4

     $m_{b}$ = (0.42 + 0.2 + 2 + 6) ÷ 4 = 8.62 ÷ 4 = 2.155

  c)  $m_{c}$ = (1.2 + 0.15 + 3.4) ÷ 3

        $m_{c}$ = 4.75 ÷ 3 = 1.58(3)

  d)  $m_{d}$ = [1.(5) + 0.1(5) + 1.5] ÷ 3

      $m_{d}$ = ($\frac{14}{9} +\frac{14}{90} +\frac{15}{10}$) ÷ 3

      $m_{d}$ = ($\frac{140}{90} +\frac{14}{90} +\frac{135}{90}$) ÷ 3

    $m_{d}$ = ($\frac{289}{90}$) ÷ 3 =  $\frac{289}{90}$ × $\frac{1}{3}$ = $\frac{289}{270}$ = 1.07