Xiao Ming achieved very good results in a fifth-grade mathematics competition (full score: 100). He multiplied his age, ranking and grades to get 3456, so how old is Xiaoming this year?
小明在一次小学五年级数学竞赛(满分100分)中取得了很好的成绩．他将自己的年龄、名次和成绩相乘得3456，则小明今年多少岁．
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