I numeri relativi Algebra

Prima le somme dentro le tre parentesi tonde:

mcm (1; 8; 4) = 8;   mcm(3; 2 ; 1) = 6;  mcm (2; 4) = 4.

[(8/8 + 7/8 - 18/8) : (- 1/16) * ( 10/6 + 3/6 - 6/6) - (- 8/4 + 7/4)] : (- 29/2) =

= [(- 3/8) * (- 16/1) * (+ 7/6)  - (- 1/4) ] : (- 29/2) =

segno della moltiplicazione:

(-) * (-) = (+);    (+) * (+) = (+);

prodotto ; si semplifica 16 con 8; resta 2  al numeratore; 

si semplifica 3 con 6; resta 2 al denominatore; 

(3 * 16 * 7) /(8 * 1 * 6) = (1 * 2 * 7) / 1 * 1 * 2) = 7/1

= [ + (3 * 16 * 7) /(8 * 1 * 6) + 1/4] : (- 29/2) =

= [+ 7/1 + 1/4 ] * (- 2/29) =

mcm(1; 4) = 4;

= [ 28/4 + 1/4] * (- 2/29) =

=  29/4 * (- 2/29)  = 

= - 1/2 .

Ciao  @lolik

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$\small \left[\left(1+\dfrac{7}{8}-\dfrac{9}{4}\right)÷\left(-\dfrac{1}{16}\right)·\left(\dfrac{5}{3}+\dfrac{1}{2}-1\right)-\left(-2+\dfrac{7}{4}\right)\right]÷\left(-\dfrac{29}{2}\right) =$

$\small = \left[\left(\dfrac{8+7-18}{8}\right)·\left(-\dfrac{16}{1}\right)·\left(\dfrac{10+3-6}{6}\right)-\left(\dfrac{-8+7}{4}\right)\right]·\left(-\dfrac{2}{29}\right) =$

$\small = \left[\left(-\dfrac{3}{\cancel8_1}\right)·\left(-\dfrac{\cancel{16}^2}{1}\right)·\dfrac{7}{6}-\left(-\dfrac{1}{4}\right)\right]·\left(-\dfrac{2}{29}\right) =$

$\small = \left[\left(-\dfrac{3}{1}\right)·\left(-\dfrac{2}{1}\right)·\dfrac{7}{6}+\dfrac{1}{4}\right]·\left(-\dfrac{2}{29}\right) =$

$\small = \left[\cancel6^1·\dfrac{7}{\cancel6_1}+\dfrac{1}{4}\right]·\left(-\dfrac{2}{29}\right) =$

$\small = \left[1·\dfrac{7}{1}+\dfrac{1}{4}\right]·\left(-\dfrac{2}{29}\right) =$

$\small = \left[7+\dfrac{1}{4}\right]·\left(-\dfrac{2}{29}\right) =$

$\small = \left[\dfrac{28+1}{4}\right]·\left(-\dfrac{2}{29}\right) =$

$\small = \dfrac{\cancel{29}^1}{\cancel4_2}·\left(-\dfrac{\cancel2^1}{\cancel{29}_1}\right) =$

$\small = \dfrac{1}{2}·\left(-\dfrac{1}{1}\right) =$

$\small = -\dfrac{1}{2}$