Bonsoir
B = 9/2 - 5/2 : 15/8
B = 9/2 - 5/2 x 8/15
B = 9/2 - 5/15 x 8/2
B = 9/2 - 5/(5 x 3) x (2 x 4)/2
B = 9/2 - 1/3 x 4
B = 9/2 - 4/3
B = (9 x 3)/(2 x 3) - (4 x 2)/(3 x 2)
B = 27/6 - 8/6
B = 19/6
