"<p>In this video we will discover the most used Python data structure which are lists, let's use it in our python program and save more lines and variables.</p> <p>Here is the code we wrote, try not to just copy it but practice and then check if you get stuck:</p> <pre> <code>listMatieres = [9.0,20,11.25,1,13.25,14.75,15.25] listCoefs= [3,2.75,4,1,2,2,1] # moyenne somme = (listMatieres[0]*listCoefs[0]) + (listMatieres[1]*listCoefs[1]) + (listMatieres[2]*listCoefs[2]) +(listMatieres[3]*listCoefs[3]) +(listMatieres[4]*listCoefs[4]) +(listMatieres[5]*listCoefs[5]) +(listMatieres[6]*listCoefs[6]) print("La somme est :") print(somme) sommeCoefs = listCoefs[0] + listCoefs[1] + listCoefs[2] +listCoefs[3]+ listCoefs[4]+listCoefs[5]+ listCoefs[6] moyenne = somme /sommeCoefs print("La moyenne est :") print(moyenne)</code></pre>"