Bonjour
A = (0,1 x 10^5 x 2,4 x 10^(-1))/(240 x (10^3)^2)
A = (1 x 10^(-1) x 10^5 x 2,4 x 10^(-1))/(240 x 10^(3*2))
A = 2,4/240 x 10^(-1+5-1)/10^6
A = (24 x 10^(-1))/(24 x 10) x 10^(3-6)
A = 10^(-1-1-3)
A = 10^(-5)
B = (3 x 10^10 x 800 x 10^(-1))/(1200 x (10^(-10))^4
B = (3 x 800 / 1200) x 10^(10-1+10*4)
B = 2400/1200 x 10^(9+40)
B = 2 x 10^49
C = (300 x 10^(-10) x 0,08 x 10^(-10))/(800 x (10^6)^3)
c = (300 x 0,08 / 800) x 10^(-10-10-6*3)
C = (3 x 8 / 800) x 10^(-20-18)
C = 3/100 x 10^(-38)
C = 3/10^2 x 10^(-38)
C = 3 x 10^(-38-2)
C = 3 x 10^(-40)