㈠ 用不同的方法简便计算808x125
方法一:808x125 =808*1000/8
=101*1000 =101000
方法二:808x125
=(800+8)*125
=800*125+8*125
=100000+1000
=101000
方法三:808x125
=808*(100+25)
=808*100*5/4
=202*5*100
=101000
请选为满意答案
=(800+8)x125
=800x125+8x125
=100000+1000
=101000
㈢ 用简便方法计算。 878x125-78×125 1000÷125÷8×25 9
878x125-78×125
=(878-78)x125 运用乘法分配律
=800x125
=100000
1000÷125÷8×25
=1000÷(125x8)x25
=1000÷1000x25
=25
99×23+23
=99x23+23x1 运用乘法分配律
=(99+1)x23
=100x23
=2300
399×25
=(400-1)x25
=400x25-1x25
=10000-25
=9975
祝学习进步。