方分米. 正确 .
【解答】解:4×3=12(立方分米);
答:它与等底等高的圆柱体的体积是 12 立方分米.
故判断为:正确.
四.计算题(35 分 ).
21.(5 分)
直接写出得数 8.8÷0.2= 2﹣1 = ×1 =
127+38=
1÷7+ = 1﹣1× = + = 1.02﹣0.43=
÷25%× = ×2÷ ×2=
【解答】
解:127+38=165 8.8÷0.2=44 2﹣1 = ×1 =1
1÷7+ =1 1﹣1× = + =1 1.02﹣0.43=0.59
÷25%× = ×2÷ ×2=4
故答案为:165,44, ,1,1, ,1 ,0.59, ,4.
22.(6 分)简算
①9 ﹣(3 +0.4)
②1.8× +2.2×25%
③ .
【解答】解:①9 ﹣(3 +0.4),
=9 ﹣3 ﹣ ,
=9 ﹣ ﹣3 ,
=9﹣3 ,
=5 ;
②1.8× +2.2×25%,
=1.8×0.25+2.2×0.25,
=(1.8+2.2)×0.25,
=4×0.25,
=1;
③ ,
= ×(1﹣ )+ ×( ﹣ )+…+ ×( ﹣ )+ ×( ﹣ ),
= ×(1﹣ + ﹣ +…+ ﹣ + ﹣ ),
= ×(1﹣ ),
= × ,
= .
23.(12 分)脱式计算
①6.25﹣40÷16×2.5
② +(4 ﹣3 )÷
③(8 ﹣10.5× )÷4
④2 ÷[5 ﹣4.5×(20%+ )].