同学们站成一行，从前往后数丁丁是第3个，从后往前数丁丁也是第3 个，这行共有多少人？;@:w7K(Z'w/~,r7]+e'q
算式：提示-K,E0S6N6q/D3F;@:w7K(Z'w/~,r7]+e'q
答：这行共有7^:e(e-a.i'n7N)X7f0z0S9M8w人;@:w7K(Z'w/~,r7]+e'q