张生种了6棵树，加上秋生种的一共15棵，秋生种了多少棵？/\4r4R1d/V7]9a;z/\8c5L+c'x;F8]*K
算式：提示4I1B3L0B*v/\4r4R1d/V7]9a;z/\8c5L+c'x;F8]*K
口答：秋生种了/u4N+@+q2^*R:_+Z'\2m9E2]棵。/\4r4R1d/V7]9a;z/\8c5L+c'x;F8]*K