问题
解答题
用简便方法计算.
4.05-2.8-0.2 3.25÷2.5÷4 5.63×49+4.37×49.
答案
(1)4.05-2.8-0.2,
=4.05-(2.8+0.2),
=4.05-3,
=1.05;
(2)3.25÷2.5÷4,
=3.25÷(2.5×4),
=3.25÷10,
=0.325;
(3)5.63×49+4.37×49,
=(5.63+4.37)×49,
=10×49,
=490.