六年级解方程专项练习 200 题(有答案) (1)x\ufe63 = , (9)2x\ufe63 x=1.2, (2) x× × = , (10)9×3\ufe631.7x=13.4, (3) \ufe634x= , (11)x\ufe6325%x=24, (4) 8×2.5\ufe632x=13.6 (12) x\ufe63 +0.2= , (5) 0.78:x=3:5, (13)0.6x+90%x=78, (6)1\ufe6320%x=0.4, (14)20%x\ufe632.4×3=0.8, (8) 1÷(x\ufe63 )=6, (15) x\ufe63 x=42, 第 1 页 共 1 页 (16)0.6x+3×2.5=67.5, (23) 4x\ufe63 =3 , (17)1 ÷(x\ufe630.45)=5 , (24)12x+7×0.3=20.1, (18)x\ufe632.25=8.25, (25) x+ x= , (19) :x=3:12, (26)x:42= , (20) x+0.8=5.6, (27) ×0.5+ x= , (21) 1.4:x=1:0.75, (28)0.8: =0.48:x, (22) x×(2\ufe63 )=24, (29)χ \ufe63 χ = , 第 2 页 共 2 页 (30)42: =χ : (39) ×3\ufe637x=1.04, (31)5x\ufe630.4=75%, (40) x\ufe631\ufe63 x=2, ( 32) 6x\ufe630.9=4.5, (41)x\ufe63 x=14, (33)2(x\ufe633)=5.8, (42)3x\ufe63 x= , (34) 1.6x=6.4, (43) = , (35) 4x\ufe633×9=29, (44)1.2: = , (36)16+8x=40, (45) = : , (37) x÷1.1=3, (46) : =x:0.8, (38) +2x= , 第 3 页 共 3 页 (47)x = +1, (55)x:0.3= : , (48)1\ufe6325%X+25%x= +25%x, (56)150%x+66=99 = (49) , (57)x+6\ufe630.8x=16 ×X= (50) , (58) (51) 5:8=x:32, (59) (52)2x+3×0.9=24.9, (60)3 ÷(X\ufe63 )=1.3 (53)5.3x\ufe632.9x= , (61) (X+0.5) :2 =(X\ufe634) : , (54) ×(7\ufe632.8x)=1.5, (62) X÷0.05=3.528, 第 4 页 共 4 页 (63)2X\ufe634×6=80, (72) (64)4×4.5\ufe633X=6.38, (73) , (65)4X\ufe637.2=10, (74)4( +x)= , (66)11.5X+X=20, (75) ×0.25+ x= , (67)3.8×12+15X=87.6, (68)6X+5=17, (76)x\ufe63 , (69)0.6×(2.5+X)=4.2, (77)200:6=x: , (70) : =X: , (78)4÷X= , (71) , (79)8(x\ufe632)=2(x+7) , 第 5 页 共 5 页 (80) :18%= , (88)3(x+4.5)=60, (89)1.6x+2.4=7.52, \ufe632x= , (81) (90)3(x\ufe630.8)=6.3, x+ x=46, (82) (91)28.4\ufe635x=5.8, (83) :x= : , (92)x: = (84) = , (85)5(3x\ufe634)\ufe632(x\ufe631)=5(2x\ufe631) (93) +2x= , (86) = , (94) x=15%, (87)8(2X\ufe637)=5(X+13) , (95) x\ufe63 x= , 第 6 页 共 6 页 (96)x+50%x=6, (104)x\ufe63 , (97) :x=0.3:12, (105)x× , (98)4x+2(8\ufe63x)=26, (106)5x+35=650, (99) x\ufe63 =0, (107)720÷3x=80, (100) + x=1, (108)3.6x\ufe630.9x=8.1, (101)x×( + )= , (109)4×4.5\ufe633x=6, (102) , (110) = , (103) , (111)6×3\ufe631.8X=7.2, 第 7 页 共 7 页 (112) ÷x= , (120)22.5\ufe630.4x=12.5, (121)x:3.5=4:2 , (113)x÷ =42, (114) x+ = , (122)x\ufe630.8x\ufe636=16, (115)7x÷3=8.19, (123) : =x:8, (116)12:0.6=x: , (124) , (117)3(x+2)=4(x+1) , (125)x:15= : , (118)3x\ufe6370%x=9.2, (126) x+ x= , (119) 6+ x=240, (127)x×50%\ufe63 x=5, 第 8 页 共 8 页 (128)1\ufe63 x= , (136) 7x÷3=8.19, (129)2.5+1 x=3 , (137) 32.8\ufe639x=17.5, (130)3 x\ufe632 =4, (138) x\ufe630.36x=16, (131)8.5\ufe633x=2 , (139) 6×7+3x=69, (132)3 ÷x=4, (140) 6x+2x\ufe6356=0, (133) x\ufe635%=17.54, (141) 3x\ufe630.45×4=2.7, (134) : = : (4\ufe63x) , (142) 5.8x\ufe634.6x=0.96, (143) 8.4÷(9\ufe63x)=3, (135) 6x+31=49, 第 9 页 共 9 页 (144) 3x÷1.2=8, (153) 7.8\ufe633x=3.6, (145)5x+28=71, (154) 6×3\ufe631.8x=7.2, (146)8.7\ufe631.2x=3.9, (155)10:x=4.5:0.8, (147)8x\ufe632.6x=37.8, (156) : =x: , (148)0.75x\ufe630.95×4=8.5, (157)X\ufe637.65=4.64, (149)54÷2+3x=72, (158)28.25\ufe63X=8.25, (150)8x\ufe632.6=37.8, (159)X\ufe63(3.6+2.97)=12.42, (151) x÷ = , (160) ÷x= , (152)x+30%x=26, (161) 14.5=5.5, 第 10 页 共 10 页 (162)x\ufe6380%x=48, (171)5 ÷x= , (163)75%x\ufe635× =6, (172) \ufe63 x= , (164)x\ufe636.8=15.4, (173)4.5× \ufe633 x=1.5, (165)1.9x=5.7, (174) (1+25%)x=0.5, (166)4.3y\ufe63y=4.6, (175)x\ufe6340%x=9, (167)5x+2.6=7.6, (176)x×20%=15.2, (168) x\ufe631.5=12.9, (178) x\ufe63 (169) 9x+5x=8.4, x= , (170) 6.8+3.2x=14.8, (179) x÷75%=3, 第 11 页 共 11 页 (180)4x\ufe63 , (188) \ufe63 =1, (181) :x= :4.5, (189)4x\ufe635×6=12, (182) (x\ufe634.5)×6=12.5, (190)8x\ufe633x=15.6, (183)27\ufe6317x=13.4, (191)30×(x÷4)=60, (184)9.6+3x=3.24×5, (192)7.2×0.5\ufe633x=1.2, (185)2x+5=5x\ufe637, (193)5x\ufe632.4×5=8, (186) 3(x\ufe632)=2\ufe635(x\ufe632) , (194) + x= ×2, (187)4x\ufe633(20\ufe63x)+4=0, (195)5x+2.4×15=66, 第 12 页 共 12 页 (196)3.2x+2.8x-x=1, (197)2.5×16-8x=12, (198)9.6-3x=6.3, (199)5(x+6)=75, (200)x÷0.7+0.9×3=4, 第 13 页 共 13 页 解方程专项练习 200 题答案: (1)x\ufe63 = , 1÷(x\ufe63 )×(x\ufe63 )=6×(x\ufe63 ) , 1=6×(x\ufe63 ) , 6x\ufe636× =1, = , , x= ; 6x\ufe633=1, 6x=4, 6x÷6=4÷6, x= (2) x× × x= , = , (9)2x\ufe63 x=1.2, x(2\ufe63 )=1.2, x=1.2, x÷ =1.2÷ , x=1; (10)9×3\ufe631.7x=13.4, 27\ufe631.7x=13.4, 27\ufe631.7x+1.7x=13.4+1.7x, 13.4+1.7x=27, 13.4+1.7x\ufe6313.4=27\ufe6313.4, 1.7x=13.6, 1.7x÷1.7=13.6÷1.7, x=8 (11)x\ufe6325%x=24, 75%x=24, 75%x÷75%=24÷75%, x=32; x×21= ×21, x=12; (3) \ufe634x= , \ufe634x+4x= +4x, = +4x ÷4=4x÷4, x= . , (4) 8×2.5\ufe632x=13.6 20\ufe632x=13.6, 13.6+2X=20, 2X=6.4, x=3.2; (5) 0.78:x=3:5, 3x=0.78×5, 3x=3.9, x=1.3 (6)1\ufe6320%x=0.4, 1\ufe6320%x+20%x=0.4+20%x, 0.4+20%x=1, 0.4+20%x\ufe630.4=1\ufe630.4, 20%x=0.6, 20%x× =0.6× x=3; (8) 1÷(x\ufe63 )=6, , (12) x\ufe63 +0.2= , x\ufe630.6= , x\ufe630.6+0.6= +0.6, x= , ÷ , x÷ = x=1 (13)0.6x+90%x=78, 第 14 页 共 14 页 1.5x=78, 1.5x÷1.5=78÷1.5, x=52; (14)20%x\ufe632.4×3=0.8, 20%x\ufe637.2=0.8, 20%x\ufe637.2+7.2=0.8+7.2, 20%x÷20%=8÷20%, x=40; (20) x+0.8=5.6, x+0.8\ufe630.8=5.6\ufe630.8, x=4.8, x× =4.8× , x=8. (21) 1.4:x=1:0.75, x=1.4×0.75, x=1.05 (22) x×(2\ufe63 )=24, x× =24, x× ÷ =24÷ , x=20; (23) 4x\ufe63 =3 , 4x\ufe63 + =3 + , 4x=4, 4x÷4=4÷4, x=1 (24)12x+7×0.3=20.1, 12x+2.1=20.1, 12x+2.1\ufe632.1=20.1\ufe632.1, 12x÷12=18÷12, x=1.5; (25) x+ x= , x= , x× , x= ; (15) x\ufe63 x=42, x=42, x÷ =42÷ , x=252 (16)0.6x+3×2.5=67.5, 0.6x+7.5=67.5, 0.6x+7.5\ufe637.5=67.5\ufe637.5, 0.6x=60, 0.6x÷0.6=60÷0.6, x=100; (17)1 ÷(x\ufe630.45)=5 , ÷(x\ufe630.45)×(x\ufe630.45)= x\ufe632.4=1.6, x\ufe632.4+2.4=1.6+2.4, x=4, (x\ufe630.45) , x÷ x= =4÷ , (18)x\ufe632.25=8.25, x\ufe632.25+2.25=8.25+2.25, x=10.5; (19) :x=3:12, 3x= ×12, 3x÷3=9÷3, x=3 (26)x:42= , 10x=42× , 10x÷10=30÷10, x=3 (27) ×0.5+ x= , 第 15 页 共 15 页 0.75+ x=3.75, 0.75+ x\ufe630.75=3.75\ufe630.75, x=3, x÷ =3÷ , x=6; (28)0.8: =0.48:x, ×0.48, 0.8x= 0.8x=0.2, 0.8x÷0.8=0.2÷0.8, x= (29)χ \ufe63 χ = , x= , x\ufe633+3=2.9+3, x=5.9; (34) 1.6x=6.4, 1.6x÷1.6=6.4÷1.6, x=4; (35) 4x\ufe633×9=29, 4x\ufe6327=29, 4x\ufe6327+27=29+27, 4x=56, 4x÷4=56÷4, x=14; (36)16+8x=40, 16+8x\ufe6316=40\ufe6316, 8x=24, 8x÷8=24÷8, x=3; (37) x÷1.1=3, x÷1.1×1.1=3×1.1, x=3.3 (38) +2x= , +2x = , 2x= , 2x÷2= ÷2, x = x=3; , (30)42: =χ : x= ; x=42× , (39) x =30 , x=50; (31)5x\ufe630.4=75%, 5x\ufe630.4+0.4=75%+0.4, 5x÷5=1.15÷5, x=0.23 ×3\ufe637x=1.04, 2.16\ufe637x=1.04, 2.16\ufe637x\ufe631.04=1.04\ufe631.04, 1.12\ufe637x=0, 7x÷7=1.12÷7, x=0.16; (40) x\ufe631\ufe63 x=2, x\ufe631=2, ( 32) 6x\ufe630.9=4.5, 6x\ufe630.9+0.9=4.5+0.9, 6x=5.4, 6x÷6=5.4÷6, x=0.9; (33)2(x\ufe633)=5.8, 2(x\ufe633)÷2=5.8÷2 x\ufe633=2.9, x\ufe631+1=2+1, x=3, x =3 x=18; (41)x\ufe63 x=14, , 第 16 页 共 16 页 x=14, x =14 , x=1 (48) 1\ufe6325%X+25%x= +25%x, 0.25x+0.25\ufe630.25=1\ufe630.25, 0.25x=0.75, x=3; = , (49) 0.25x=1.25×1.6, 0.25x÷0.25=1.25×1.6÷0.25, x=8; ×X= , , (50) ×X÷ = x= ; (51) 5:8=x:32, 8x=5×32, 8x÷8=5×32÷8, x=20 (52)2x+3×0.9=24.9, 2x+2.7=24.9, 2x+2.7\ufe632.7=24.9\ufe632.7, 2x÷2=22.2÷2, x=11.1; (53)5.3x\ufe632.9x= , : , 2.4x÷2.4= ÷2.4, , 2.4x= , x=18; (42)3x\ufe63 x= x= x , = x= (43) = , ; , , 2.4x=72×0.26, 2.4x=18.72, 2.4x÷2.4=18.72÷2.4, x=7.8; (44)1.2: = , x=1.2×5, x=6, x =6 x=9; (45) = , x=18× x= x , x= ; = x=12; (46) x= x : =x:0.8, , (54) ×(7\ufe632.8x)=1.5, ×(7\ufe632.8x) =1.5 , ×0.8, =0.04 , x=0.2; (47)x x = +1, × , 7\ufe632.8x=2.1, 7\ufe632.8x+2.8x=2.1+2.8x, 7\ufe632.1=2.1+2.8x\ufe632.1, 4.9÷2.8=2.8x÷2.8, x=1.75; (55)x:0.3= : , x=0.3× , × = 第 17 页 共 17 页 x = x= , (56) 150%x+66=99 1.5x+66=99 1.5x=33 x=22 (57)x+6\ufe630.8x=16 0.2x+6=16 0.2x=10 x=50 (58) 2X\ufe6324+24=80+24, 2X=104, 2X÷2=104÷2, X=52; (64)4×4.5\ufe633X=6.38, 18\ufe633X=6.38, 18\ufe633X+3X=6.38+3X, 6.38+3X=18, 6.38+3X\ufe636.38=18\ufe636.38, 3X=11.62, 3X÷3=11.62÷3, X= ; x=14.4 (59) 0.55x=5.5 x=10 (60)3 3 ÷(X\ufe63 )=1.3 ÷(X\ufe63 )×(x\ufe63 )=1.3×(x\ufe63 ) , 3 3 =1.3x\ufe630.78, +0.78=1.3x\ufe630.78+0.78, 4.68=1.3x, 4.68÷1.3=1.3x÷1.3, x=3.6; (61) (X+0.5) :2 =(X\ufe634) : , ×(x\ufe634)=(x+0.5)× , x\ufe63 ×4= x+ ×0.5, x, (65)4X\ufe637.2=10, 4X\ufe637.2+7.2=10+7.2, 4X=17.2, 4X÷4=17.2÷4, X=4.3; (66)11.5X+X=20, 12.5X=20, 12.5X÷12.5=20÷12.5, X=1.6; (67)3.8×12+15X=87.6, 45.6+15X=87.6, 45.6+15X\ufe6345.6=87.6\ufe6345.6, 15X=42, 15X÷15=42÷15, X=2.8 (68)6X+5=17, 6x+5\ufe635=17\ufe635, 6x÷6=12÷6, x=2; (69)0.6×(2.5+X)=4.2, 0.6×(2.5+X)÷0.6=4.2÷0.6, 2.5+x=7, 2.5+x\ufe632.5=7\ufe632.5, x=4.5; x\ufe6310\ufe63 x= x+ 2.25x\ufe6310+10=0.125+10, 2.25x÷2.25=10.125÷2.25, x=4.5 (62) X÷0.05=3.528, X÷0.05×0.05=3.528×0.05, X=0.1764; (63)2X\ufe634×6=80, 2X\ufe6324=80, (70) : =X: x= × x÷ = x=0.6 , , , 第 18 页 共 18 页 (71) , , , , , ; x= ; (77)200:6=x: (72) 6x=200× , , , , ; (73) , , , , , 6x÷6=480÷6, x=80 (78)4÷X= , 4÷X×X= X, X=4, X÷ =4÷ , X=10; (79)8(x\ufe632)=2(x+7) , 8X\ufe6316=2X+14, 6X\ufe6316=14, 6X=30, X=5; (74)4( +x)= +4x= +4x\ufe63 , = \ufe63 , (80) , 4x=4, x=1; :18%= , X=0.18×6.5, X=1.17, X=7.8 \ufe632x= , (81) \ufe632x+2x= +2x, +2x= , +2x\ufe63 = \ufe63 , 2x= , (75) ×0.25+ x= , 0.2+ x= , 0.2+ x\ufe630.2= \ufe630.2, x= x= , (76)x\ufe63 , 第 19 页 共 19 页 2x÷2= x= ÷2, ; x= (87)8(2X\ufe637)=5(X+13) , 16x\ufe6356=5x+65, 16x\ufe6356\ufe635x=5x+65\ufe635x, 11x\ufe6356=65, 11x\ufe6356+56=65+56, 11x=121, 11x÷11=121÷11, x=11, x+ x=46, (82) x( + )=46, x=46, x÷ =46÷ , x=40; (83) :x= : , x= × , x= x÷ = x= , ÷ , ; (88)3(x+4.5)=60, 3(x+4.5)÷3=60÷3, x+4.5=20, x+4.5\ufe634.5=20\ufe634.5, x=15.5 (89)1.6x+2.4=7.52, 1.6x+2.4\ufe632.4=7.52\ufe632.4, 1.6x=5.12, 1.6x÷1.6=5.12÷1.6, x=3.2; (90)3(x\ufe630.8)=6.3, 3x\ufe632.4=6.3, 3x\ufe632.4+2.4=6.3+2.4, 3x=8.7, 3x÷3=8.7÷3, x=2.9; (91)28.4\ufe635x=5.8, 28.4\ufe635x+5x=5.8+5x, 5.8+5x=28.4, 5.8+5x\ufe635.8=28.4\ufe635.8, 5x=22.6, 5x÷5=22.6÷5, x=4.52 (84) = , 1.6x=6.4×2, 1.6x=12.8, 1.6x÷1.6=12.8÷1.6, x=8 (85)5(3x\ufe634)\ufe632(x\ufe631)=5(2x\ufe631) 15x\ufe6320\ufe632x+2=10x\ufe635, 13x\ufe6318=10x\ufe635, 13x\ufe6318\ufe6310x=10x\ufe635\ufe6310x, 3x\ufe6318=\ufe635, 3x\ufe6318+18=\ufe635+18, 3x=13, 3x÷3=13÷3, x= (86) = , ; (92) x: = 25x= ×3, 25x= , 25x÷25= x= ; , 3(6x\ufe631)=64, 18x\ufe633=64, 18x\ufe633+3=64+3, 18x=67, 18x÷18=67÷18, 第 20 页 共 20 页 (93) +2x= , +2x = 2x=0, x=0; (94) x=15%, , (100) + x=1, + x\ufe63 =1\ufe63 , x= , x× = × , x=1; (101)x×( + )= x= x× , = × , x= , (102) , , , 3x÷3= x= ; (103) , , , x=20; (104)x\ufe63 , , x= (105)x× x× x= (106)5x+35=650, 第 21 页 共 21 页 x×x=15%x, 0.15x=0.15, 0.15x÷0.15=0.15÷0.15, x=1; (95) x\ufe63 x= x= x , = x= . , , . (96)x+50%x=6, 1.5x=6, 1.5x÷1.5=6÷1.5, x=4; (97) :x=0.3:12, 0.3x= , , 0.3x÷0.3=9÷0.3, x=30; (98)4x+2(8\ufe63x)=26, 4x+16\ufe632x=26, 2x+16=26, 2x+16\ufe6316=26\ufe6316, 2x÷2=10÷2, x=5 (99) x\ufe63 =0, x\ufe63 + =0+ , x= , x×3= ×3, x= ; , ; , , 5x+35\ufe6335=650\ufe6335, 5x=615, 5x÷5=615÷5, x=123; (107)720÷3x=80, 720÷3x×3x=80×3x, 240x=720, 240x÷240=720÷240, x=3; (108)3.6x\ufe630.9x=8.1, (3.6\ufe630.9)x=8.1, 2.7x=8.1, 2.7x÷2.7=8.1÷2.7, x=3; (109)4×4.5\ufe633x=6, 18\ufe633x=6, 18\ufe633x+3x=6+3x, 6+3x=18, 6+3x\ufe636=18\ufe636, 3x=12, 3x÷3=12÷3, x=4 (110) = , (114) x+ = x+ \ufe63 = , \ufe63 , x= , x÷ = ÷ , x= (115)7x÷3=8.19, 7x÷3×3=8.19×3, 7x=24.57, 7x÷7=24.57÷7, x=3.51; (116)12:0.6=x: , 0.6x=12× , 0.6x=6, 0.6x÷0.6=6÷0.6, x=10; (117)3(x+2)=4(x+1) , 3x+6=4x+4, 3x+6\ufe633x=4x+4\ufe633x, x+4=6, x+4\ufe634=6\ufe634, x=2 2.5x=10×0.8, 2.5x÷2.5=8÷2.5, x=3.2; (111)6×3\ufe631.8X=7.2, 18\ufe631.8X=7.2, 18\ufe631.8X+1.8X=7.2+1.8X, 7.2+1.8X=18, 7.2+1.8X\ufe637.2=18\ufe637.2, 1.8X=10.8, 1.8X÷1.8=10.8÷1.8, X=6 (112) ÷x= , x= x= ÷ , ; (118)3x\ufe6370%x=9.2, 3x\ufe630.7x=9.2, 2.3x=9.2, 2.3x÷2.3=9.2÷2.3, x=4; (119) 6+ x=240, 6+ x\ufe636=240\ufe636, x=234, x÷ =234÷ , (113)x÷ =42, , x=42× x=9; x=390 (120)22.5\ufe630.4x=12.5, 22.5\ufe630.4x+0.4x=12.5+0.4x, 12.5+0.4x=22.5, 第 22 页 共 22 页 12.5+0.4x\ufe6312.5=22.5\ufe6312.5, 0.4x÷0.4=10÷0.4, x=25; (121)x:3.5=4:2 , 2 x=3.5×4, 2 x÷2 =14÷2 , x=6 (122)x\ufe630.8x\ufe636=16, 0.2x\ufe636=16, 0.2x\ufe636+6=16+6, 0.2x÷0.2=22÷0.2, x=110; (123) : =x:8, x=8× , x× =8× × , x=4; x=30; (128)1\ufe63 x= , 1\ufe63 x+ x= + x, + x=1, + x\ufe63 =1\ufe63 , x× = × , x= ; (129)2.5+1 x=3 , 2.5+1 x\ufe632.5=3 \ufe632.5, x= x× = x= , × , (124) , (130)3 x\ufe632 =4, 3 x\ufe632 +2 =4+2 , 3 x=6 , 3 x÷3 =6 ÷3 , 0.06x=2×0.015, 0.06x÷0.06=0.03÷0.06, x=0.5; (125)x:15= : , x=15× , x= x×6=15× ×6, x=40; (126) x+ x= x= x× , = × , , ; (131)8.5\ufe633x=2 , 8.5\ufe633x+3x=2 +3x, 3x+2 =8.5, 3x+2 \ufe632 =8.5\ufe632 , 3x=6, 3x÷3=6÷3, x=2; (132)3 ÷x=4, x= ; (127)x×50%\ufe63 x=5, x=5, 3 ÷x×x=4×x, x×6=5×6, 第 23 页 共 23 页 4x=3 , 4x÷4=3 ÷4, x= (133) x\ufe635%=17.54, 解: x\ufe635%+5%=17.54+5%, x =17.59 , x=23 ; (134) : = : (4\ufe63x) , 解: 4 x= , x, + x , x=3 (135) 6x+31=49, 6x+31\ufe6331=49\ufe6331, 6x=18, 6x÷6=18÷6, x=3; (136) 7x÷3=8.19, 7x÷3×3=8.19×3, 7x=24.57, 7x÷7=24.57÷7, x=3.51; (137) 32.8\ufe639x=17.5, 32.8\ufe639x+9x=17.5+9x, 17.5+9x=32.8, 17.5+9x\ufe6317.5=32.8\ufe6317.5, 9x=15.3, 9x÷9=15.3÷9, x=1.7; (138) x\ufe630.36x=16, (1\ufe630.36)x=16, 0.64x=16, 0.64x÷0.64=16÷0.64, x=25; (139) 6×7+3x=69, , 2\ufe63 x+ x= 2\ufe63 = x 42+3x=69, 42+3x\ufe6342=69\ufe6342, 3x=27, 3x÷3=27÷3, x=9; (140) 6x+2x\ufe6356=0, (6+2)x\ufe6356+56=0+56, 8x=56, 8x÷8=56÷8, x=7 (141) 3x\ufe630.45×4=2.7, 3x\ufe631.8=2.7, 3x\ufe631.8+1.8=2.7+1.8, 3x=4.5, 3x÷3=4.5÷3, x=1.5; (142) 5.8x\ufe634.6x=0.96, 1.2x=0.96, 1.2x÷1.2=0.96÷1.2, x=0.8; (143) 8.4÷(9\ufe63x)=3, 9\ufe63x=8.4÷3, 9\ufe63x=2.8, x=9\ufe632.8, x=6.2; (144) 3x÷1.2=8, 3x÷1.2×1.2=8×1.2, 3x=9.6, 3x÷3=9.6÷3, x=3.2 (145)5x+28=71, 5x+28\ufe6328=71\ufe6328, 5x=43, 5x÷5=43÷5, x=8.6; (146)8.7\ufe631.2x=3.9, 8.7\ufe631.2x+1.2x\ufe633.9=3.9+1.2x\ufe633.9, 4.8=1.2x, 1.2x=4.8, 1.2x÷1.2=4.8÷1.2, x=4; (147)8x\ufe632.6x=37.8, 5.4x=37.8, 5.4x÷5.4=37.8÷5.4, x=7; (148)0.75x\ufe630.95×4=8.5, 0.75x\ufe633.8=8.5, 第 24 页 共 24 页 0.75x\ufe633.8+3.8=8.5+3.8, 0.75x=12.3, 0.75x÷0.75=12.3÷0.75, x=16.4, ; (149)54÷2+3x=72, 27+3x=72, 27+3x\ufe6327=72\ufe6327, 3x=45, 3x÷3=45÷3, x=15; (150)8x\ufe632.6=37.8, 8x\ufe632.6+2.6=37.8+2.6, 8x=40.4, 8x÷8=40.4÷8, x=5.05 4.5x=8, 4.5x÷4.5=8÷4.5, x= ; , , (156) : =x: x= × x= x÷ = x= , ÷ , (151) x÷ = x÷ × = x= , ×4, , × , x×4= x= ; (157)X\ufe637.65=4.64, X\ufe637.65+8.67=4.64+7.65, X=12.29; (158)28.25\ufe63X=8.25, 28.25\ufe63X+X=8.25+X, X+8.25=28.25, X+8.25\ufe638.25=28.25\ufe638.25, X=20; (159)X\ufe63(3.6+2.97)=12.42, X\ufe636.57=12.42, X\ufe636.57+6.57=12.42+6.57, X=18.99 (160) ÷x= , ÷x×x= ×x, x= , x÷ = ÷ , x= × , x= ; (161) 14.5=5.5, (152)x+30%x=26, (1+30%)x=26, 1.3x=26, 1.3x÷1.3=26÷1.3, x=20; (153) 7.8\ufe633x=3.6, 7.8\ufe633x+3x=3.6+3x, 3.6+3x=7.8, 3.6+3x\ufe633.6=7.8\ufe633.6, 3x=4.2, 3x÷3=4.2÷3, x=1.4 (154) 6×3\ufe631.8x=7.2, 18\ufe631.8x=7.2, 18\ufe631.8x+1.8x=7.2+1.8x, 18=7.2+1.8x, 18\ufe637.2=7.2+1.8x\ufe637.2, 10.8=1.8x, 10.8÷1.8=1.8x÷1.8, x=6; (155)10:x=4.5:0.8, 4.5x=10×0.8, 14.5+14.5=5.5+14.5, =20, ×8=20×8, x=160 (162)x\ufe6380%x=48, 第 25 页 共 25 页 (1\ufe630.8)x=48, 0.2x=48, 0.2x÷0.2=48÷0.2, x=240; 5 ÷ = x= x÷ ; , (172) \ufe63 x= , (163)75%x\ufe635× =6, 0.75x\ufe633=6, 0.75x\ufe633+3=6+3, 0.75x=9, 0.75x÷0.75=9÷0.75, x=12 (164)x\ufe636.8=15.4, x\ufe636.8+6.8=15.4+6.8, x=22.2; (165)1.9x=5.7, 1.9x÷1.9=5.7÷1.9, x=3; (166)4.3y\ufe63y=4.6, 3.3y=4.6, 3.3y÷3.3=4.6÷3.3, y= ; \ufe63 x+ x= + x, = + x, \ufe63 = + x\ufe63 , = x, ÷ = = x÷ , x=1; (173)4.5× \ufe633 x=1.5, 1.5\ufe633.5x=1.5, 1.5\ufe633.5x+3.5x=1.5+3.5x, 1.5=1.5+3.5x, 1.5\ufe631.5=1.5+3.5x\ufe631.5, 0=3.5x, 0÷3.5=3.5x÷3.5, x=0 (174) (1+25%)x=0.5, 1.25x=0.5, 1.25x÷1.25=0.5÷1.25, x=0.4; (175)x\ufe6340%x=9, 0.6x=9, 0.6x÷0.6=9÷0.6, x=15; (176)x×20%=15.2, x×20%÷20%=15.2÷20%, x=76 (177)30x\ufe6330=180, 30x\ufe6330+30=180+30, 30x=210, 30x÷30=210÷30, x=7; (178) x\ufe63 x= x= , , (167)5x+2.6=7.6, 5x+2.6\ufe632.6=7.6\ufe632.6, 5x=5, 5x÷5=5÷5, x=1 (168) x\ufe631.5=12.9, x\ufe631.5+1.5=12.9\ufe631.5, x=11.4; (169) 9x+5x=8.4, 14x=8.4, 14x÷14=8.4÷14, x=0.6; (170) 6.8+3.2x=14.8, 6.8\ufe636.8+3.2x=14.8\ufe636.8, 3.2x=8, 3.2x÷3.2=8÷3.2, x=2.5 (171)5 ÷x= 5 ÷x×x= 5 = x, , x, 第 26 页 共 26 页 x÷ = x= ÷ , ; (179) x÷75%=3, x÷75%×75%=3×75%, x= , x÷ = ÷ , x= (180)4x\ufe63 , 4x\ufe636=2.4, 4x=2.4+6, x=8.4÷4, x=2.1. (181) :x= :4.5, x=4.5× , x=2, x=2× , x=5 (182) (x\ufe634.5)×6=12.5, 6x\ufe634.5×6=12.5, 6x\ufe6327=12.5, 6x\ufe6327+27=12.5+27, 6x=39.5, 6x÷6=39.5÷6, x=6 (183)27\ufe6317x=13.4, 27\ufe6317x+17x=13.4+17x, 13.4+17x=27, 13.4+17x\ufe6313.4=27\ufe6313.4, 17x=13.6, 17x÷17=13.6÷17, x=0.8; (184)9.6+3x=3.24×5, 9.6+3x\ufe639.6=16.2\ufe639.6, 3x=6.6, ; 3x÷3=6.6÷3, x=2.2 (185)2x+5=5x\ufe637, 2x+5\ufe632x=5x\ufe637\ufe632x, 3x\ufe637=5, 3x\ufe637+7=5+7, 3x=12, 3x÷3=12÷3, x=4; (186) 3(x\ufe632)=2\ufe635(x\ufe632) , 3x\ufe636=12\ufe635x, 3x\ufe636+5x=12\ufe635x+5x, 8x\ufe636=12, 8x\ufe636+6=12+6, 8x=18, 8x÷8=18÷8, x=2.25; (187)4x\ufe633(20\ufe63x)+4=0, 7x\ufe6356=0, 7x\ufe6356+56=0+56, 7x=56, 7x÷7=56÷7, x=8; (188) ( \ufe63 \ufe63 =1, )×24=1×24, 6(y+2)\ufe634(2y\ufe633)=24, 30\ufe632y=24, 30\ufe632y+2y=24+2y, 2y+24=30, 2y+24\ufe6324=30\ufe6324, 2y=6, 2y÷2=6÷2, y=3 (189)4x\ufe635×6=12, 4x\ufe6330=12, 4x\ufe6330+30=12+30, 4x=42, 4x÷4=42÷4, x=10.5; (190)8x\ufe633x=15.6, 5x=15.6, 5x÷5=15.6÷5, x=3.12; 第 27 页 共 27 页 (191)30×(x÷4)=60, 30×(x÷4)÷30=60÷30, x÷4=2, x÷4×4=2×4, x=8; (192)7.2×0.5\ufe633x=1.2, 3.6\ufe633x=1.2, 3.6\ufe633x+3x=1.2+3x, 3x+1.2=3.6, 3x+1.2\ufe631.2=3.6\ufe631.2, 3x=2.4, 3x÷3=2.4÷3, x=0.8 (193)5x\ufe632.4×5=8, 5x\ufe6312+12=8+12, 5x=20, 5x÷5=20÷5, x=4, 6.3+3x=9.6, 6.3+3x-6.3=9.6-6.3, 3x=3.3, 3x÷3=3.3÷3, x=1.1; (199)5(x+6)=75, 5x+30=75, 5x+30-30=75-30, 5x=45, 5x÷5=45÷5, x=9; (200)x÷0.7+0.9×3=4, x÷0.7+2.7=4, x÷0.7+2.7-2.7=4-2.7, x÷0.7=1.3, x÷0.7×0.7=1.3×0.7, x=0.91. (194) + x= ×2, x= , x× = × x= . , (195)5x+2.4×15=66, 5x+36=66, 5x+36-36=66-36, 5x=30, 5x÷5=30÷5, x=6; (196)3.2x+2.8x-x=1, 5x=1, 5x÷5=1÷5, x=0.2; (197)2.5×16-8x=12, 40-8x=12, 40-8x+8x=12+8x, 8x+12=40, 8x+12-12=40-12, 8x=28, 8x÷8=28÷8, x=3.5. (198)9.6-3x=6.3, 9.6-3x+3x=6.3+3x, 第 28 页 共 28 页