解题思路:(1)、(3)据四则混合运算法则计算即可;
(2)可将式中66×0.208变为6.6×2.08后据分配律进行简算;
(4)式中(12.5+1.25+0.125)×80可据分配律进行简算.
(1)2.9×1.4+2×0.16
=4.06+0.32,
=4.38;
(2)5.4×2.08+66×0.208-2.08
=5.4×2.08+6.6×2.08-2.08,
=(5.4+6.6-1)×2.08,
=11×2.08,
=22.88;
(3)30.8÷[14-(9.85+1.07)]
=30.8÷[14-10.92]
=30.8÷3.08,
=10;
(4)[(12.5+1.25+0.125)×80-999]÷0.03
=[(12.5×80+1.25×80+0.125×80)-999]÷0.03,
=[(1000+100+10)-999]÷0.03,
=[1110-999]÷0.03,
=111÷0.03,
=3700.
点评:
本题考点: 运算定律与简便运算;小数四则混合运算.
考点点评: 解答本题要注意分析式中数据,找到合适的简算方法.