直接寫(xiě)出得數(shù).
1.2+3.58=
500÷25÷8=
0.99+99×0.99=
69×11=
1.25×8=
0.875×4=
解:(1)1.2+3.58=4.78,
(2)500÷25÷8=2.5;
(3)0.99+99×0.99=99;
(4)69×11=759;
(5)1.25×8=10;
(6)0.875×4=3.5.
分析:(1)根據(jù)小數(shù)加法的計(jì)算法則進(jìn)行計(jì)算,注意小數(shù)點(diǎn)對(duì)齊;
(2)根據(jù)小數(shù)連續(xù)除以兩個(gè)數(shù)等于除以這兩個(gè)數(shù)的乘積簡(jiǎn)算,即500÷(25×8);
(3)根據(jù)乘法的分配律把它變成0.99×(1+99),再進(jìn)行計(jì)算;
(4)根據(jù)乘法的分配律把它變成69×(10+1),進(jìn)行計(jì)算;
(5)、(6)根據(jù)小數(shù)乘法的計(jì)算方法直接計(jì)算.
點(diǎn)評(píng):本題考查了基本的計(jì)算,根據(jù)運(yùn)算法則求解,計(jì)算時(shí)要注意小數(shù)點(diǎn)的位置.