1、22.54+(-4.4+(-12.54)+4.4(2/3-1/2)-(1/3-5/6)2.4-(-3/5)+(3.1)+4/5(-6/13)+(-7/13)-(-2)3/4-(-11/6)+(-7/3)22.54+(-4.4+(-12.54)+4.4=10(2/3-1/2)-(1/3-5/6)=2/32.4-(-3/5)+(3.1)+4/5=6.9(-6/13)+(-7/13)-(-2)=13/4-(-11/6)+(-7/3)=1/42、计算:(1) 4.2+5.78.4+10 ; (2)6.13.74.9+1.8;(3) +1; (4) + + ;31 41653213、计算:(1) 216
2、 157+348+512678; (2)81.26293.8+8.74+111;(3) 4 +1 17 2 ; (4)2.25+3 12 8 ;32141874312534、计算:(1)12(18)+(7)15;(2) 4028 (19)+(24)( 32);(3)4.7(8.9)7.5+(6);(4) +( )( ) ;3261421解:(1) 4.2+5.7 8.4+10=5.7+104.28.4=15.712.6=3.1(2)6.13.7 4.9+1.8=6.1+1.83.74.9=7.98.6=0.7(4) + + = + = =4165321653241234(3) +1= +1 =
3、 =3、解:(1)216157+348+512678=348+512 216157678=8601051=191(2)81.6293.8+8.74+111=81.26+8.74+111293.8=201 293.8= 92.8(3)4 +1 17 2 =4 17 2 +1 =24 +1 =321187341871361222 87(4)2.25+3 12 8 =2.25+3 12 8 =620 =1442525494、解:(1)12 (18)+(7)15=12+18715=30 22=8(2) 4028 (19)+(24)( 32)=4028+1924+32=402824+19+32=92+5
4、1= 41(3)4.7(8.9)7.5+(6)=4.7+8.97.56=13.6 13.5=0.1(4) +( )( ) = + = +32614213641236124= + =142.计算:(1) 4 ; (2)5 10.8;3172(3)0.120.54 ; (4)4.72+16.425.2802.(1)3 (2)5.3 (3)0.57 (4)6.421计算:(1)5( 2)(3); (2)3.44.78.35;(3) (4) 5327 2175.15.0参考答案1(1)4;(2)7.05;(3) ;(4)3.531210计算:(1) )(2; (2)(2.2)+3.8;(3) 4+(
5、5 61); (4)(5 61)+0;(5)(+2 )+ (2.2); (6)( 52)+ (+0.8);(7)(6)+8+(4)+12 ; (8) 317)(41(9)0.36+ ( 7.4)+0 .3+(0.6)+0.64;(10)9+ ( 7)+10+ ( 3)+(9);(11) )412(8)5.()8;(12) )23(5712 10(1) 65 ;(2)1.6; (3) 65 ; (4) 65 ; (5)0; (6) 32;(7)10;(8)0; (9)6.7; (10)0; (11)16; (12)3 1 1.计算:(1)2317(7)+(16)(2) +( )1+32531(3)(26.54)+(6.4)18.54+6 .4(4)(4 )(5 )+(4 )387281(5)0+1( 1)( )(+5)( )+477参考答案1. 解:(1)原式 =2317+716=23+71716=30 33=3(2)原式=( + 1)+( )=32151(3)原式=(26.54)18.54+(6.4)+6.4=(26.54)18.54=45.08(4)原式=(4 )+5 +(4 )3 =(4 4 3 )+587287182=12 +5 =61(5)原式=1 (1)+ 5+ +4=1(1+ )5+4=1(5)77+4=10