Exercise 1. A l'aide. Merci !

Exercice 1 : 

A= 3/4 + 5/4 + 15/6
A= (3 X 6)/(4 X 6) + (5 X 6)/(4 X 6) + (15 X 4)/(6 X 4)
A= 18/24 + 30/24 + 60/24
A= 108/24
A= 9/2 ou 4,5

B= (15 X 10⁻³ X 7 X (10³)²)/3 X 10⁴
B= (15 X 7 X 10⁻³ X 10⁶)/3 X 10⁴
B= (105 X 10³)/(3 X 10⁴)
B= 15000/30000
B= 0,5 soit 5,0 X 10⁻¹

Si tu as des questions, n'hésites pas! :)