Answers

2014-06-30T17:28:33+08:00
4(12)+4(8)
--------------
      4

= 48 + 32
  -------------
        4

= 80
   ----
    4

= 20
0
2014-06-30T17:33:28+08:00
4(12)+4(8)/4
=(48+32)/4
=80/4
=20
0