Bonsoir
Coefficient de proportionnalité :
4 | 9
12 | 27
12/4 = (3 x 4)/4 = 3
27/9 = (3 x 9)/9 = 3
14 | 4
4,2 | 1,2
4,2/14 = 42/140 = (14 x 3)/(14 x 10) = 3/10
1,2/4 = 12/40 = (4 x 3)/(4 x 10) = 3/10
140 | 266
420 | 798
420/140 = (140 x 3)/140 = 3
798/266 = (266 x 3)/266 = 3
12 .....| 9
22,8 | 17,1
22,8/12 = 228/120 = (19 x 12)/(10 x 12) = 19/10 = 1,9
17,1/9 = 171/90 = (19 x 9)/(10 x 9) = 19/10 = 1,9