hasil dari...jwb no 8 dan 9

8. 3/4 + 2/5=23/20
9. 4/5 : 3 = 4/5×1/3=4/15

8. D
    3/4 + 2/5 =    15 + 8       =   23 /20  
                         _______
                             20

9.  D
    4/5 : 3 = 4/5 : 3/1 = 4/5 x 1/3 = 4/15