计算:1÷3+1/3÷5+1/5÷7+1/7÷9+1/9÷11+1/11÷13+1/13÷15

问题描述:

计算:1÷3+1/3÷5+1/5÷7+1/7÷9+1/9÷11+1/11÷13+1/13÷15