Réponse :
bonjour
Explications étape par étape :
C=-2x 25 x (-5) × (-4) × (-9)
=2x-5x-25 x -4x-9
=250 x-4 x-9
= 1000 x -9
=-9000
D = -0,03 × (-2) × 7 × (-100) × 0,5
=-0.03x-100 x 0.5 x-2x7
=3x0.5 x-2x7
=1.5x-2 x7
=-3x7
= -21
E = -5x (-1,25) × (-3) × 20 × (-8)
=-5 x 20 x-1.25 x-3x-8
=-100 x -1.25 x-3x-8
=125 x -3 x-8
=-375x-8
=3000
F = -2,5 × (-7,5) × 0,4 × (-5) × (-8) × (-2)
=-25.x0.4 x-7.5x-2 x-5x-8
=-1x 15 x40
=-600
G= 8× (-1,25) × 0,1 × (-2) × (-0,5) × (-1)
= -1.25x-2 x8x-05
=2.5x-4 x0.1 x-1
=1
