问题
解答题
脱式计算,能简算的要简算.
|
答案
(1)
×5 11
+7 9
×7 9
,6 11
=(
+5 11
)×6 11
,7 9
=1×
,7 9
=
;7 9
(2)51×101,
=51×(100+1),
=51×100+51×1,
=5100+51,
=5151;
(3)10.25-3.75-6.25+7.75,
=(10.25+7.75)-(3.75+6.25),
=18-10,
=8;
(4)35×12+350÷70,
=420+5,
=425;
(5)3+0.7÷[(
-5 6
)×24],1 4
=3+0.7÷[
×24-5 6
×24],1 4
=3+0.7÷[20-6],
=3+0.7÷14,
=3+0.05,
=3.05;
(6)
÷1 3
×6 5
,9 10
=
×5 18
,9 10
=
.1 4