Hello
3.589 = 3589 * 10-³ = 3589/10³
1/8 = 125 * 10-³ = 125 / 10³
9.91 * 10-⁹ = 991/10¹¹
123.436 * 10-¹⁰ = 123436 * 10-¹³ = 123436/10¹³
Bonne journée