脱式计算(能简便算的要简便算) (1)0.01+1.01×99 (2)26×20.2-8.4-1.8 (3)89.3×43+38×89.3+893×1.9 (4)10.01×101-10.01.
问题描述:
脱式计算(能简便算的要简便算)
(1)0.01+1.01×99
(2)26×20.2-8.4-1.8
(3)89.3×43+38×89.3+893×1.9
(4)10.01×101-10.01.
答
(1)0.01+1.01×99,
=0.01+1.01×(100-1),
=0.01+1.01×100-1.01×1,
=101+0.01-1.01,
=100;
(2)26×20.2-8.4-1.8,
=26×(20+0.2)-(8.4+1.8),
=520+5.2-10.2,
=525.2-10.2,
=515;
(3)89.3×43+38×89.3+893×1.9,
=89.3×43+38×89.3+89.3×19,
=89.3×(43+38+19),
=89.3×100,
=8930;
(4)10.01×101-10.01,
=10.01×101-10.01×1,
=10.01×(101-1),
=10.01×100,
=1001.