bonjour
A = 6 x 10 ² sur 12 x 10 ⁻² = 0.5 x 10 ⁴ = 5 000 = 5 x 10 ³
B = 105 x 10 ² sur 21 x 10 ⁻¹ = 5 x 10 ³ = 5 000
C = 22.5 x 10 ² sur 15 x 10 ⁻⁴ = 1.5 x 10 ⁶ = 1 500 000
D = 4.42 x 10 ⁴ sur 0.2 x 10 ⁸ = 22.1 x 10 ⁻⁴ = 0.00221 = 2.21 x 10 ⁻³
E = 60 x 10 ³ sur 120 x 10 ⁻³ = 0.5 x 10 ⁶ = 500 000 = 5 x 10 ⁵
A = 2/7 - 63/63 = 18/63 - 63/63 = - 45/63 = - 5 /7
B = 6 x 10 ³ sur 15 x 10 ⁴ = 6/15 x 10 ⁻¹ = 3/5 x 10 ⁻¹
C = ( 12/20 - 5/20) : ( 3/3 + 2/3) = 7/20 : 1/3 = 7/20 x 3 = 21/20
