12,7+5,89+1,3=12,7+1,3+5,89=14+5,89=19,89
38,6+2,09+7,91=38,6+10=48,6
5,75+7,8+4,25+1,2=5,75+4,25+7,8+1,2=10+9=19
7,34+0,45+2,66+0,55=7,34+2,66+0,45+0,55=10+1=11
12,7 + 5,89 +1,3
=(12,7+1,3)+5,89
=14 + 5,89
=19,89
38,6+2,09+7,91
=38,6+(2,09+7,91)
=38,8+10
=48,8