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1、(1)x(2) x 六年级解方程专项练习六年级解方程专项练习 200200 题(有答案)题(有答案)= ,(9)2x x=1.2,(10)931.7x=13.4,= ,(3)4x= ,(4) 82.52x=13.6(5) 0.78:x=3:5,(6)120%x=0.4,(8) 1(x )=6,11)x25%x=24,12) x +0.2= ,13)0.6x+90%x=78,14)20%x2.43=0.8,15) x x=42,(16)0.6x+32.5=67.5,(17)1 (x0.45)=5 ,(23) 4x =3 ,(24)12x+70.3=20.1,(18)x2.25=8.25,(19)
2、 :x=3:12,(20) x+0.8=5.6,(21) 1.4:x=1:0.75, (22) x(2 )=24,25) x+ x= ,26)x:42=,27)0.5+ x=,28)0.8:=0.48:x,29) = ,(30)42: =:(31)5x0.4=75%,(39)37x=1.04,(40) x1 x=2,( 32) 6x0.9=4.5,(33)2(x3)=5.8,(34) 1.6x=6.4,(35) 4x39=29,(36)16+8x=40,(37) x1.1=3,(38) +2x= ,41)x x=14,42)3x x=,43)=,44)1.2: = ,45)=:,46): =x
3、:0.8,(47)x= +1,(55)x:0.3= : ,(56)150%x+66=99(48)125%X+25%x= +25%x,=,(49)X=,(50)(51) 5:8=x:32,(52)2x+30.9=24.9,(53)5.3x2.9x= ,(54) (72.8x)=1.5,57)x+60.8x=1658)59)60)3(X )=1.361) (X+0.5) :2 =(X4) : ,62) X0.05=3.528,(63)2X46=80,(64)44.53X=6.38,(65)4X7.2=10,(72)(73),(66)11.5X+X=20,(67)3.812+15X=87.6,(68
4、)6X+5=17,(69)0.6(2.5+X)=4.2,(70) : =X:,(71),74)4( +x)=,75) 0.25+ x= ,76)x,77)200:6=x:,78)4X= ,79)8(x2)=2(x+7) ,(80):18%=,2x= ,(81)(88)3(x+4.5)=60,(89)1.6x+2.4=7.52,x+ x=46,(82)(83) :x= : ,(84)=,(85)5(3x4)2(x1)=5(2x1)(86)= ,(87)8(2X7)=5(X+13) ,90)3(x0.8)=6.3,91)28.45x=5.8,92)x: =93) +2x= ,94)x=15%,95
5、) x x=,(96)x+50%x=6,(97) :x=0.3:12,(98)4x+2(8x)=26,(104)x(105)x,(99) x =0,(100) + x=1,(101)x( + )=,(102),(103),106)5x+35=650,107)7203x=80,108)3.6x0.9x=8.1,109)44.53x=6,110)=,111)631.8X=7.2,(112)x= ,(113)x=42,(120)22.50.4x=12.5,(121)x:3.5=4:2 ,(114) x+ =,(115)7x3=8.19,(116)12:0.6=x: ,(117)3(x+2)=4(x+
6、1) ,(118)3x70%x=9.2,(119) 6+ x=240,122)x0.8x6=16,123) : =x:8,124),125)x:15= : ,126) x+ x=,127)x50% x=5,(128)1 x= ,(129)2.5+1 x=3 ,(136) 7x3=8.19,(137) 32.89x=17.5,(130)3 x2 =4,(131)8.53x=2 ,(132)3 x=4,(133) x5%=17.54,(134) : = : (4x) ,(135) 6x+31=49,0.36x=16,7+3x=69,56=0,0.454=2.7,4.6x=0.96,(9x)=3,(
7、138) x(139) 6(140) 6x+2x(141) 3x(142) 5.8x(143) 8.4(144) 3x1.2=8,(145)5x+28=71,(146)8.71.2x=3.9,(153) 7.83x=3.6,(154) 631.8x=7.2,(155)10:x=4.5:0.8,(147)8x2.6x=37.8,(148)0.75x0.954=8.5,(149)542+3x=72,(150)8x2.6=37.8,(151) x =,(152)x+30%x=26,156) : =x:,157)X7.65=4.64,158)28.25X=8.25,159)X(3.6+2.97)=12
8、.42,160) x= ,161)14.5=5.5,(162)x80%x=48,(163)75%x5 =6,(164)x6.8=15.4,(171)5 x=,(172) x= ,(165)1.9x=5.7,(166)4.3yy=4.6,(167)5x+2.6=7.6,(168) x1.5=12.9,(169) 9x+5x=8.4,(170) 6.8+3.2x=14.8,173)4.5 3 x=1.5,174) (1+25%)x=0.5,175)x40%x=9,176)x20%=15.2,178) xx=,179) x75%=3,(180)4x,(188)=1,(181) :x= :4.5,(1
9、89)4x56=12,(182) (x4.5)6=12.5,(183)2717x=13.4,(184)9.6+3x=3.245,(185)2x+5=5x7,(186) 3(x2)=25(x2) ,(187)4x3(20 x)+4=0,190)8x3x=15.6,191)30(x4)=60,192)7.20.53x=1.2,193)5x2.45=8,194) + x= 2,195)5x+2.415=66,(196)3.2x+2.8x-x=1,(197)2.516-8x=12,(198)9.6-3x=6.3,(199)5(x+6)=75,(200)x0.7+0.93=4,解方程专项练习解方程专项练
10、习 200200 题题答案:答案:(1)x= ,= , x= ;(2) x = ,x= ,x21= 21, x=12;(3)4x= ,4x+4x= +4x,= +4x,4=4x4, x=(4) 82.52x=13.6 202x=13.6, 13.6+2X=20, 2X=6.4, x=3.2;(5) 0.78:x=3:5, 3x=0.785, 3x=3.9, x=1.3(6)120%x=0.4, 120%x+20%x=0.4+20%x, 0.4+20%x=1,0.4+20%x0.4=10.4, 20%x=0.6, 20%x=0.6, x=3;(8) 1(x )=6,1(x )(x )=6(x )
11、 , 1=6(x ) , 6x6 =1, 6x3=1, 6x=4, 6x6=46, x=(9)2x x=1.2, x(2 )=1.2,x=1.2,x =1.2 , x=1;(10)931.7x=13.4, 271.7x=13.4, 271.7x+1.7x=13.4+1.7x, 13.4+1.7x=27,13.4+1.7x13.4=2713.4, 1.7x=13.6, 1.7x1.7=13.61.7, x=8(11)x25%x=24, 75%x=24, 75%x75%=2475%, x=32;(12) x +0.2= ,x0.6= ,x0.6+0.6= +0.6,x=,x = , x=1(13)
12、0.6x+90%x=78, 1.5x=78, 1.5x1.5=781.5, x=52;(14)20%x2.43=0.8, 20%x7.2=0.8, 20%x7.2+7.2=0.8+7.2, 20%x20%=820%, x=40;(15) x x=42,x=42,x =42 , x=252(16)0.6x+32.5=67.5, 0.6x+7.5=67.5, 0.6x+7.57.5=67.57.5, 0.6x=60, 0.6x0.6=600.6, x=100;(17)1 (x0.45)=5 ,(x0.45)(x0.45)=(x0.45) ,x2.4=1.6,x2.4+2.4=1.6+2.4,x=4
13、,x=4, x=(18)x2.25=8.25, x2.25+2.25=8.25+2.25, x=10.5;(19) :x=3:12, 3x= 12, 3x3=93, x=3(20) x+0.8=5.6,x+0.80.8=5.60.8,x=4.8,x =4.8 , x=8(21) 1.4:x=1:0.75, x=1.40.75, x=1.05 (22) x(2 )=24, x =24, x =24 , x=20;(23) 4x =3 ,4x + =3 + , 4x=4, 4x4=44, x=1(24)12x+70.3=20.1, 12x+2.1=20.1, 12x+2.12.1=20.12.1,
14、 12x12=1812, x=1.5;(25) x+ x= ,x= ,x, x= ;(26)x:42=, 10 x=42 , 10 x10=3010, x=3(27)0.5+ x=, 0.75+ x=3.75, 0.75+ x0.75=3.750.75,x=3,x =3 , x=6;(28)0.8:=0.48:x, 0.8x=0.48, 0.8x=0.2, 0.8x0.8=0.20.8, x=(29) = ,x= ,x=, x=3;(30)42: = :x=42 ,x=30, x=50;(31)5x0.4=75%, 5x0.4+0.4=75%+0.4, 5x5=1.155, x=0.23( 3
15、2) 6x0.9=4.5, 6x0.9+0.9=4.5+0.9, 6x=5.4, 6x6=5.46, x=0.9;(33)2(x3)=5.8,2(x3)2=5.82 x3=2.9, x3+3=2.9+3, x=5.9;(34) 1.6x=6.4,1.6x1.6=6.41.6, x=4;(35) 4x39=29, 4x27=29, 4x27+27=29+27, 4x=56, 4x4=564, x=14;(36)16+8x=40,16+8x16=4016, 8x=24, 8x8=248, x=3;(37) x1.1=3,x1.11.1=31.1, x=3.3(38) +2x= ,+2x=, 2x=
16、 , 2x2= 2, x= ;(39)37x=1.04, 2.167x=1.04, 2.167x1.04=1.041.04, 1.127x=0, 7x7=1.127, x=0.16;(40) x1 x=2,x1=2,x1+1=2+1,x=3,x=3, x=18;(41)x x=14,x=14,x=14, x=18;(42)3x x=,x=,x=, x=;(43)=, 2.4x=720.26, 2.4x=18.72,2.4x2.4=18.722.4, x=7.8;(44)1.2: = ,x=1.25,x=6,x=6, x=9;(45)=:,x=18,x=,x=, x=12;(46): =x:0.
17、8,x=0.8,x=0.04, x=0.2;(47)x= +1, x = , x=1(48) 125%X+25%x= +25%x,0.25x+0.250.25=10.25, 0.25x=0.75, x=3;=,(49) 0.25x=1.251.6,0.25x0.25=1.251.60.25, x=8;X=,(50)X =, x= ;(51) 5:8=x:32, 8x=532,8x8=5328, x=20(52)2x+30.9=24.9, 2x+2.7=24.9, 2x+2.72.7=24.92.7, 2x2=22.22, x=11.1;(53)5.3x2.9x= , 2.4x= , 2.4x2
18、.4= 2.4, x= ;(54) (72.8x)=1.5,(72.8x)=1.5, 72.8x=2.1, 72.8x+2.8x=2.1+2.8x, 72.1=2.1+2.8x2.1, 4.92.8=2.8x2.8, x=1.75;(55)x:0.3= : ,x=0.3 ,x=, x=(56)150%x+66=99 1.5x+66=99 1.5x=33 x=22(57)x+60.8x=16 0.2x+6=16 0.2x=10 x=50(58) x=14.4(59) 0.55x=5.5 x=10(60)3(X )=1.33(X )(x )=1.3(x ) , 3=1.3x0.78, 3+0.78
19、=1.3x0.78+0.78, 4.68=1.3x, 4.681.3=1.3x1.3, x=3.6;(61) (X+0.5) :2 =(X4) : ,(x4)=(x+0.5) ,x4= x+ 0.5,x10 x= x+x, 2.25x10+10=0.125+10, 2.25x2.25=10.1252.25, x=4.5(62) X0.05=3.528,X0.050.05=3.5280.05, X=0.1764;(63)2X46=80, 2X24=80, 2X24+24=80+24, 2X=104, 2X2=1042, X=52;(64)44.53X=6.38, 183X=6.38, 183X+
20、3X=6.38+3X, 6.38+3X=18,6.38+3X6.38=186.38, 3X=11.62, 3X3=11.623, X=;(65)4X7.2=10,4X7.2+7.2=10+7.2, 4X=17.2, 4X4=17.24, X=4.3;(66)11.5X+X=20, 12.5X=20,12.5X12.5=2012.5, X=1.6;(67)3.812+15X=87.6, 45.6+15X=87.6,45.6+15X45.6=87.645.6, 15X=42, 15X15=4215, X=2.8(68)6X+5=17, 6x+55=175, 6x6=126, x=2;(69)0.6
21、(2.5+X)=4.2,0.6(2.5+X)0.6=4.20.6, 2.5+x=7, 2.5+x2.5=72.5, x=4.5;(70) : =X:,x= ,x =, x=0.6(71),;(72) x=(77)200:6=x: 6x=200,;, 6x6=4806,;(73),(74)4( +x)=,+4x=,+4x=, 4x=4, x=1;(75) 0.25+ x= , 0.2+ x= , 0.2+ x0.2= 0.2,x=, x=(76)x,78)4X= ,XX= X,X=4,X =4 ,;79)8(x2)=2(x+7) ,16=2X+14,16=14,;80):18%=,X=0.186
22、.5,X=1.17,2x= ,81)2x+2x= +2x,+2x= ,+2x = , x=80( 4 X=10( 8X 6X 6X=30 X=5( X=7.8( 2x= 2x2= x=2,; x=x+ x=46,(82) x( + )=46,x=46,x=46,(87)8(2X7)=5(X+13) , 16x56=5x+65, 16x565x=5x+655x, 11x56=65, 11x56+56=65+56, 11x=121, 11x11=12111, x=11,(88)3(x+4.5)=60, x=40;(83) :x= : ,x= ,x=,x = , x=;(84)=, 1.6x=6.4
23、2, 1.6x=12.8,1.6x1.6=12.81.6, x=8(85)5(3x4)2(x1)=5(2x1) 15x202x+2=10 x5, 13x18=10 x5, 13x1810 x=10 x510 x, 3x18=5, 3x18+18=5+18, 3x=13, 3x3=133, x=;(86)= , 3(6x1)=64, 18x3=64, 18x3+3=64+3, 18x=67, 18x18=6718,(x+4.5)3=603,4.5=204.5,89)1.6x+2.4=7.52,2.4=7.522.4,1.6=5.121.6,;90)3(x0.8)=6.3,2.4=6.3,2.4+
24、2.4=6.3+2.4,3=8.73,;91)28.45x=5.8,5x+5x=5.8+5x,5.8=28.45.8,5=22.65,92)x: =3,25=,; 3 x+4.5=20 x+4.5 x=15.5( 1.6x+2.4 1.6x=5.12 1.6x x=3.2( 3x 3x 3x=8.7 3x x=2.9( 28.4 5.8+5x=28.4 5.8+5x 5x=22.6 5x x=4.52( 25x= 25x= 25x x=(93) +2x= ,+2x=, 2x=0, x=0;(94)x=15%,xx=15%x, 0.15x=0.15,0.15x0.15=0.150.15, x=1
25、;(95) x x=,x=,x=, x= (96)x+50%x=6, 1.5x=6, 1.5x1.5=61.5, x=4;(97) :x=0.3:12, 0.3x=, 0.3x0.3=90.3, x=30;(98)4x+2(8x)=26, 4x+162x=26, 2x+16=26, 2x+1616=2616, 2x2=102, x=5(99) x =0,x + =0+ ,x= ,x3= 3, x= ;(100) + x=1,+ x =1 ,x= ,x = , x=1;(101)x( + )=,x=,x=, x=(102), 3x3=, x= ;(103), x=20;(104)x, x=;(1
26、05)x,x, x=(106)5x+35=650, 5x+3535=65035, 5x=615, 5x5=6155, x=123;(107)7203x=80, 7203x3x=803x, 240 x=720, 240 x240=720240, x=3;(108)3.6x0.9x=8.1,(3.60.9)x=8.1, 2.7x=8.1, 2.7x2.7=8.12.7, x=3;(109)44.53x=6, 183x=6, 183x+3x=6+3x, 6+3x=18, 6+3x6=186, 3x=12, 3x3=123, x=4(110)=, 2.5x=100.8, 2.5x2.5=82.5, x
27、=3.2;(111)631.8X=7.2, 181.8X=7.2, 181.8X+1.8X=7.2+1.8X, 7.2+1.8X=18, 7.2+1.8X7.2=187.2, 1.8X=10.8, 1.8X1.8=10.81.8, X=6(112)x= , x= , x=;(113)x=42, x=42, x=9;(114) x+ =,x+ = ,x= ,x = , x=(115)7x3=8.19, 7x33=8.193, 7x=24.57, 7x7=24.577, x=3.51;(116)12:0.6=x: , 0.6x=12 , 0.6x=6, 0.6x0.6=60.6, x=10;(11
28、7)3(x+2)=4(x+1) , 3x+6=4x+4, 3x+63x=4x+43x, x+4=6, x+44=64, x=2(118)3x70%x=9.2, 3x0.7x=9.2, 2.3x=9.2, 2.3x2.3=9.22.3, x=4;(119) 6+ x=240,6+ x6=2406,x=234,x =234 , x=390(120)22.50.4x=12.5, 22.50.4x+0.4x=12.5+0.4x, 12.5+0.4x=22.5, 12.5+0.4x12.5=22.512.5, 0.4x0.4=100.4, x=25;(121)x:3.5=4:2 , 2 x=3.54,
29、x=30;(128)1 x= , 1 x+ x= + x,+ x=1,+ x =1 ,x = , 2 x2 =142 , x=6(122)x0.8x6=16, 0.2x6=16, 0.2x6+6=16+6, 0.2x0.2=220.2, x=110;(123) : =x:8,x=8 ,x =8 , x=4;(124), 0.06x=20.015, 0.06x0.06=0.030.06, x=0.5;(125)x:15= : ,x=15 ,x6=15 6, x=40;(126) x+ x=,x=,x=, x= ;(127)x50% x=5,x=5,x6=56,;129)2.5+1 x=3 ,x2
30、.5=3 2.5,x=,x = ,130)3 x2 =4,x2 +2 =4+2 ,x=6 ,x3 =6 3 ,;131)8.53x=2 ,3x+3x=2 +3x,=8.5,2 =8.52 ,3=63,;132)3 x=4,xx=4x, x=( 2.5+1 x=( 3 3 3 x=( 8.5 3x+2 3x+2 3x=6 3x x=2( 3 4x=3 , 4x4=3 4, x=(133) x5%=17.54,解: x5%+5%=17.54+5%,x=17.59, x=23;(134) : = : (4x) ,解:4x=, 2 x+ x=x, 2+ x,= x, x=3(135) 6x+31=49
31、, 6x+3131=4931, 6x=18, 6x6=186, x=3;(136) 7x3=8.19,7x33=8.193, 7x=24.57, 7x7=24.577, x=3.51;(137) 32.89x=17.5, 32.89x+9x=17.5+9x, 17.5+9x=32.8,17.5+9x17.5=32.817.5, 9x=15.3, 9x9=15.39, x=1.7;(138) x0.36x=16,(10.36)x=16, 0.64x=16,0.64x0.64=160.64, x=25;(139) 67+3x=69, 42+3x=69, 42+3x42=6942, 3x=27, 3
32、x3=273, x=9;(140) 6x+2x56=0,(6+2)x56+56=0+56, 8x=56, 8x8=568, x=7(141) 3x0.454=2.7, 3x1.8=2.7, 3x1.8+1.8=2.7+1.8, 3x=4.5, 3x3=4.53, x=1.5;(142) 5.8x4.6x=0.96, 1.2x=0.96, 1.2x1.2=0.961.2, x=0.8;(143) 8.4(9x)=3, 9x=8.43, 9x=2.8, x=92.8, x=6.2;(144) 3x1.2=8, 3x1.21.2=81.2, 3x=9.6, 3x3=9.63, x=3.2(145)5
33、x+28=71, 5x+2828=7128, 5x=43, 5x5=435, x=8.6;(146)8.71.2x=3.9,8.71.2x+1.2x3.9=3.9+1.2x3.9, 4.8=1.2x, 1.2x=4.8, 1.2x1.2=4.81.2, x=4;(147)8x2.6x=37.8, 5.4x=37.8, 5.4x5.4=37.85.4, x=7;(148)0.75x0.954=8.5, 0.75x3.8=8.5, 0.75x3.8+3.8=8.5+3.8, 0.75x=12.3, 0.75x0.75=12.30.75, x=16.4, ;(149)542+3x=72, 27+3x
34、=72, 27+3x27=7227, 3x=45, 3x3=453, x=15;(150)8x2.6=37.8, 8x2.6+2.6=37.8+2.6, 8x=40.4, 8x8=40.48, x=5.05(151) x =,x = ,x=,x4=4, x= ;(152)x+30%x=26,(1+30%)x=26, 1.3x=26, 1.3x1.3=261.3, x=20;(153) 7.83x=3.6, 7.83x+3x=3.6+3x, 3.6+3x=7.8, 3.6+3x3.6=7.83.6, 3x=4.2, 3x3=4.23, x=1.4(154) 631.8x=7.2, 181.8x=
35、7.2, 181.8x+1.8x=7.2+1.8x, 18=7.2+1.8x, 187.2=7.2+1.8x7.2, 10.8=1.8x, 10.81.8=1.8x1.8, x=6;(155)10:x=4.5:0.8, 4.5x=100.8, 4.5x=8, 4.5x4.5=84.5, x=;(156) : =x:,x= ,x=,x = , x=(157)X7.65=4.64,X7.65+8.67=4.64+7.65, X=12.29;(158)28.25X=8.25, 28.25X+X=8.25+X, X+8.25=28.25, X+8.258.25=28.258.25, X=20;(159
36、)X(3.6+2.97)=12.42, X6.57=12.42, X6.57+6.57=12.42+6.57, X=18.99(160) x= ,xx= x,x= ,x = , x= , x= ;(161)14.5=5.5,14.5+14.5=5.5+14.5,=20,8=208, x=160(162)x80%x=48,(10.8)x=48, 0.2x=48, 0.2x0.2=480.2, x=240;(163)75%x5 =6, 0.75x3=6, 0.75x3+3=6+3, 0.75x=9, 0.75x0.75=90.75, x=12(164)x6.8=15.4, x6.8+6.8=15.
37、4+6.8, x=22.2;(165)1.9x=5.7,1.9x1.9=5.71.9, x=3;(166)4.3yy=4.6, 3.3y=4.6, 3.3y3.3=4.63.3, y=;(167)5x+2.6=7.6, 5x+2.62.6=7.62.6, 5x=5, 5x5=55, x=1(168) x1.5=12.9, x1.5+1.5=12.91.5, x=11.4;(169) 9x+5x=8.4, 14x=8.4, 14x14=8.414, x=0.6;(170) 6.8+3.2x=14.8,6.86.8+3.2x=14.86.8, 3.2x=8, 3.2x3.2=83.2, x=2.5
38、(171)5 x=, 5 xx=x, 5 =x, 5 =x, x=;(172) x= , x+ x= + x,= + x, = + x ,= x, = = x , x=1;(173)4.5 3 x=1.5, 1.53.5x=1.5, 1.53.5x+3.5x=1.5+3.5x, 1.5=1.5+3.5x, 1.51.5=1.5+3.5x1.5, 0=3.5x, 03.5=3.5x3.5, x=0(174) (1+25%)x=0.5, 1.25x=0.5, 1.25x1.25=0.51.25, x=0.4;(175)x40%x=9, 0.6x=9, 0.6x0.6=90.6, x=15;(176
39、)x20%=15.2,x20%20%=15.220%, x=76(177)30 x30=180, 30 x30+30=180+30, 30 x=210, 30 x30=21030, x=7;(178) xx=,x=,x = x= ,;(179) x75%=3,x75%75%=375%,x= , 3x3=6.63, x=2.2(185)2x+5=5x7, 2x+52x=5x72x, 3x7=5, 3x7+7=5+7, 3x=12, 3x3=123, x=4;(186) 3(x2)=25(x2) , 3x6=125x, 3x6+5x=125x+5x,x = , x=(180)4x, 4x6=2.4
40、, 4x=2.4+6, x=8.44, x=2.1(181) :x= :4.5,x=4.5 ,x=2, x=2 , x=5(182) (x4.5)6=12.5, 6x4.56=12.5, 6x27=12.5, 6x27+27=12.5+27, 6x=39.5, 6x6=39.56, x=6;(183)2717x=13.4, 2717x+17x=13.4+17x, 13.4+17x=27,13.4+17x13.4=2713.4, 17x=13.6, 17x17=13.617, x=0.8;(184)9.6+3x=3.245, 9.6+3x9.6=16.29.6, 3x=6.6,6=12,6+6=
41、12+6,8=188,;187)4x3(20 x)+4=0,56=0,56+56=0+56,7=567,;188)=1,)24=124,(y+2)4(2y3)=24,2y=24,2y+2y=24+2y,24=3024,2=62,189)4x56=12,30=12,30+30=12+30,4=424,;190)8x3x=15.6,5=15.65,; 8x 8x 8x=18 8x x=2.25( 7x 7x 7x=56 7x x=8( 6 30 30 2y+24=30 2y+24 2y=6 2y y=3( 4x 4x 4x=42 4x x=10.5( 5x=15.6 5x x=3.12(191)3
42、0(x4)=60, 30(x4)30=6030, x4=2, x44=24, x=8;(192)7.20.53x=1.2, 3.63x=1.2, 3.63x+3x=1.2+3x, 3x+1.2=3.6, 3x+1.21.2=3.61.2, 3x=2.4, 3x3=2.43, x=0.8(193)5x2.45=8, 5x12+12=8+12, 5x=20, 5x5=205, x=4,(194) + x= 2,x= ,x= , x=(195)5x+2.415=66, 5x+36=66, 5x+36-36=66-36,5x=30,5x5=305,x=6;(196)3.2x+2.8x-x=1, 5x=
43、1, 5x5=15, x=0.2;(197)2.516-8x=12, 40-8x=12, 40-8x+8x=12+8x, 8x+12=40, 8x+12-12=40-12, 8x=28, 8x8=288, x=3.5(198)9.6-3x=6.3, 9.6-3x+3x=6.3+3x, 6.3+3x=9.6,6.3+3x-6.3=9.6-6.3, 3x=3.3, 3x3=3.33, x=1.1;(199)5(x+6)=75,5x+30=75,5x+30-30=75-30,5x=45,5x5=455,x=9;(200)x0.7+0.93=4,x0.7+2.7=4,x0.7+2.7-2.7=4-2.7,x0.7=1.3,x0.70.7=1.30.7,x=0.91