bonsoir j'ai besoin de votre aide svp, repondez que di vs savez

question 1
2kg => 1,80 (2×0.90)
5kg => 4,50 (5×0.90)
10kg => 7,20 (10×0.90-20%)
20kg => 14.40 (20×0.90-20%)
30kg => 21,60 (30×0.90-20%)
40kg => 28.80 (40×0.90-20%)
50kg => 25 (50×0.50)
60kg => 30 (60×0.50)
70kg => 35 (70×0.50)
80kg => 40 (80×0.50)