问题
解答题
直接写得数. ①3451÷17×(323-299)=______ ②22.9×7.34+2.29×26.6=______ ③16
④48.48-23
⑤〔1,9-1.9×(1
|
答案
①3451÷17×(323-299)
=3451÷17×24,
=203×24,
=4872;
②22.9×7.34+2.29×26.6
=2.29×73.4+2.29×26.6,
=(73.4+26.6)×2.29,
=100×2.29,
=229;
③16
-(27 11
-12 13
)4 11
=16
-27 11
+12 13
,4 11
=16
+17 11
-24 11
,2 13
=18-2
,2 13
=15
;1 3
④48.48-23
+3111 20
-36.4513 25
=48.48-23.55+31.52-36.45,
=48.48+31.52-(23.55+36.45),
=80-60,
=20.
⑤[1.9-1.9×(1
-1.9)]÷39 10 4 5
=[1.9-1.9×(1.9-1.9)]÷
,19 5
=[1.9-1.9×0]×
,5 19
=1.9×
,5 19
=0.5.