×2=
×8=
×5=
1× =
×6=
×7=
×4=
0× =
× =
× = ×
×16× =
×( × )=
48×( - )=
× + × =
34× =
× × ×8 × - ×
( - )× × ×8×
分析:妈妈的年龄=()× ;小红的年龄=()× 21c
;