题目

Mistakes due to (care) may have serious consequences. 答案：【1】carelessness观察如下的运算规律：15×15＝1×2×100+25＝225   25×25＝2×3×100+25＝625 35×35＝3×4×100+25＝1225……依据规律， 第4个算式应为：________