问题
解答题
用简便方法计算.
7×8×125
25×48
39+39×39.
答案
(1)7×8×125
=7×(8×125)
=7×1000
=7000;
(2)25×48
=25×4×12
=100×12
=1200;
(3)39+39×39
=(1+39)×39
=40×39
=1560.
用简便方法计算.
7×8×125
25×48
39+39×39.
(1)7×8×125
=7×(8×125)
=7×1000
=7000;
(2)25×48
=25×4×12
=100×12
=1200;
(3)39+39×39
=(1+39)×39
=40×39
=1560.