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用简便方法计算.19×8×12538+129+711900÷4÷2599×78+80.

题目详情
用简便方法计算.
19×8×125
38+129+71
1900÷4÷25 99×78+80.
▼优质解答
答案和解析
(1)19×8×125,
=19×(8×125),
=19×1000,
=19000;

(2)38+129+71,
=38+(129+71),
=38+200,
=238;

(3)1900÷4÷25,
=1900÷(4×25),
=1900÷100,
=19;

(4)99×78+80,
=99×78+78+2,
=(99+1)×78+2,
=100×78+2,
=7800+2,
=7802.