bonjour
4.54 milliards = 4 .54 x 10 ^ 9
40 075 , 017 = 4.0 075 017 x 10 ^ 7
510 067 420 = 5 , 100 674 20 x 10 ^ 8
5 972 x 10 ^21 = 5 .972 x 10 ^3 x 10 ^ 21 = 5.972 x 10 ^ 24
1 083 207 x 10 ^ 4 = 1.083 207 x 10 ^ 6 x 10 ^ 4 = 1.083 207 x 10 ^ 10
7 300 millions = 7.3 x 10 ^ 3 x 10 ^ 6 = 7.3 x 10 ^ 9
