求28乘以38加56乘以81的简便计算方法?
问题描述：
求28乘以38加56乘以81的简便计算方法?
答
28*38+56*81 =28*38+28*2*81 =28*（38+162） =28*200 =5600
求28乘以38加56乘以81的简便计算方法?
28*38+56*81 =28*38+28*2*81 =28*（38+162） =28*200 =5600