计算(1+19\39×1)+(1+19\39×2)+(1+19\39×3)+……+(1+19\39×12用简便方法计算,
问题描述:
计算(1+19\39×1)+(1+19\39×2)+(1+19\39×3)+……+(1+19\39×12用简便方法计算,
答
计算(1+19\39×1)+(1+19\39×2)+(1+19\39×3)+……+(1+19\39×12用简便方法计算,