问题
解答题
怎样简便就怎样算.
(
|
答案
(1)
×9 11
×7 15
=11 3
;7 5
(2)
×5 7
+6 13
×7 13
,5 7
=(
+6 13
)×7 13
,5 7
=1×
,5 7
=
;5 7
(3)
×87+13 88
,13 88
=
×(87+1),13 88
=
×88,13 88
=13;
(4)(
+1 3
)×3×5,2 5
=
×3×5+1 3
×3×5,2 5
=5+6,
=11.