18/20+8/15= combien svp

18/20 + 8/15
= 18 x 3 / 20 x 3 + 8 x 4  / 15 x 4
= 54/60  + 32/60
= 86/60
= 2 x 43 / 2 x 30
= 43/30

18/20 + 8/15 =

9/10 + 8/15 =

(9*3)/(10*3) + (8*2)/(15*2) =

27/30 + 16/30 =

43/30