Bonjour,
A=
-2/5 * 15/3 = -30/15
= -30/15 +2/15 = -28/15
B=
(4*1)/(5*4) = 4/20 = 2/10 = 1/5
1/5 + 2/5 = 3/5
C=
1/3 - 4/3 = -3/3 = -1
-1*2/5 =
(-1 *2) /5 = -2/5
