您现在的位置是:首页 > 学科知识查询 > 小学数学题库

计算.能简算的要简算 7.26+3.2÷2.514.6-4.6×2.80.8+0.8+-+0.8+15×0.215个0.814.5×1024.05÷0.5-1.149.99×99+9.99.

编辑:chaxungu时间:2026-04-27 07:53:41分类:小学数学题库

计算,能简算的要简算
7.26+3.2÷2.514.6-4.6×2.80.8+0.8+…+0.8+15×0.215个0.8
14.5×1024.05÷0.5-1.149.99×99+9.99.
解:(1)7.26+3.2÷2.5,
=7.26+1.28,
=8.54;

(2)14.6-4.6×2.8,
=14.6-12.88,
=1.72;

(3)0.8+0.8+…+0.8+15×0.2(15个0.8),
=0.8×15+3,
=0.8×5×3+3,
=12+3,
=15;

(4)14.5×102,
=14.5×(100+2),
=14.5×100+29,
=1450+29,
=1479;

(5)4.05÷0.5-1.14,
=8.1-1.14,
=6.96;

(6)9.99×99+9.99,
=9.99×(99+1),
=99.9×100,
=9990.
分析:(1)先算除法,再算加法;
(2)先算乘法,再算减法;
(3)把原式变为0.8×15+3,计算即可;
(4)把102看作100+2,运用乘法分配律简算;
(5)先算除法,再算减法;
(6)运用乘法分配律简算.
点评:考查了小数的四则混合运算,注意运算顺序和运算法则,灵活运用所学的运算律简便计算.