1)AB兩數的和是48,B是A的4倍多3,問A是多少?
2)有五個數,首3個的平均是35,尾3個的平均是27,5個數之和是150,求第三個數。
3)有糖26粒,A比B多60%,問A有幾粒
4)200平方米的水柱入長40米,闊25米的水池中,水面上升多少米?
5)有一盒子,用1CM厚的木料做成,外壁長22CM,闊12CM,TALL 11CM,求容積
小學數學題X5
2007-02-16 9:04 pm
回答 (7)
2007-02-16 9:22 pm
✔ 最佳答案
(1)B是A的4倍多3,即B=4A+3
A+(4A+3)=48
5A+3=48
5A=45
A=9
(2)
設這五個數是A,B,C,D,E
(A+B+C)/3=35
即A+B+C=105
(C+D+E)/3=27
即C+D+E=81
五個數之和是150
即A+B+C+D+E=81
(A+B+C)+(C+D+E)-(A+B+C+D+E)=C
C=105+81-150=36
所以C=36
(3)
設B有B粒,則A有(1+60%)B
B+(1+60%)B=26
2.6B=26
B=10
所以A有10(1+60%)=16粒
(4)
相信水柱本身是不會用200平方米,閣下應指200立方米
水面上升:
200/(40x25)
=0.2(米)
(5)
容積:
22x12x11-(22-2)x(12-2)x(11-1)
=2904-2000
=904(ml)
2007-02-16 13:24:14 補充：
對不起,第五題有錯誤:容積:如果是開口盒:(22-2)x(12-2)x(11-1)=2000ml如果是閉口盒:(22-2)x(12-2)x(11-2)=1800ml
2007-02-17 12:21 am
1)A=11.25
2)37,35,33,27,21
3)18
4)5米
5)1800CM
2)37,35,33,27,21
3)18
4)5米
5)1800CM
2007-02-16 9:53 pm
1)A=9
2)36
3)18
4)5米
5)1800CM
2)36
3)18
4)5米
5)1800CM
2007-02-16 9:30 pm
1.
A + B = 48 --- (1)
B = 4A + 3 --- (2)
A + 4A +3 = 48
5A + 45
A = 9
2.
X1 + X2 + X3 + X4 + X5 = 150 --- (1)
( X1 + X2 + X3 ) / 3 = 35 ----------- (2)
( X3 + X4 + X5 ) / 3 = 27 ----------- (3)
From (2):
X1 + X2 + X3 = 105 ------ (4)
From (3):
X3 + X4 + X5 = 81--------- (5)
(4) + (5):
X1 + X2 + 2(X3) + X4 + X5 = 186 --- (6)
(6) - (1):
X3 = 36
3.
A + B = 26
A = B x ( 1 + 0.6 ) = 1.6B
1.6B + B = 26
2.6B = 26
B = 10
A = 16
A + B = 48 --- (1)
B = 4A + 3 --- (2)
A + 4A +3 = 48
5A + 45
A = 9
2.
X1 + X2 + X3 + X4 + X5 = 150 --- (1)
( X1 + X2 + X3 ) / 3 = 35 ----------- (2)
( X3 + X4 + X5 ) / 3 = 27 ----------- (3)
From (2):
X1 + X2 + X3 = 105 ------ (4)
From (3):
X3 + X4 + X5 = 81--------- (5)
(4) + (5):
X1 + X2 + 2(X3) + X4 + X5 = 186 --- (6)
(6) - (1):
X3 = 36
3.
A + B = 26
A = B x ( 1 + 0.6 ) = 1.6B
1.6B + B = 26
2.6B = 26
B = 10
A = 16
2007-02-16 9:28 pm
1) 由於 B= 4A+3，把這代入 A+B=48的算式中，就是
A+4A+3=48
5A+3=48
5A=45
A=9
2) (35x3+27.5x3)-150=37.5
3) A=1.6B (多了60%)
代入A+B=26就是
1.6B+B=26
2.6B=26
B=10
A+B=26，如B=10，
A=16
4) (40x25)/200=0.2m
5)(你是求容量嗎？)
（減去木料的厚度）(22-1)x(12-1)x(11-1)
=21x11x10
=2310
A+4A+3=48
5A+3=48
5A=45
A=9
2) (35x3+27.5x3)-150=37.5
3) A=1.6B (多了60%)
代入A+B=26就是
1.6B+B=26
2.6B=26
B=10
A+B=26，如B=10，
A=16
4) (40x25)/200=0.2m
5)(你是求容量嗎？)
（減去木料的厚度）(22-1)x(12-1)x(11-1)
=21x11x10
=2310
2007-02-16 9:27 pm
1)A=11.25
2)37,35,33,27,21
3)18
4)5米
5)1800CM
2007-02-16 13:31:41 補充：
A=9not11.25
2)37,35,33,27,21
3)18
4)5米
5)1800CM
2007-02-16 13:31:41 補充：
A=9not11.25
2007-02-16 9:19 pm
1)A+B=48 & 4B+3=A
A=39,B=9;
2)五個數 a b c d e
(a+b+c)/3=35 && (c+d+e)/3=27 & a+b+c+d+e=150------------------(2)
a+b+2c+d+e=35*3+27*3=186--------------------(1)
(1)-(2) c=35
3)A+B=26 & A*1.6 = B
2.6A=26
A=10
4) 200*h1=h2*40*25
h1=5*h2
5米
5) (22-2)*(12-2)*(11-2)
=1800cm^3
A=39,B=9;
2)五個數 a b c d e
(a+b+c)/3=35 && (c+d+e)/3=27 & a+b+c+d+e=150------------------(2)
a+b+2c+d+e=35*3+27*3=186--------------------(1)
(1)-(2) c=35
3)A+B=26 & A*1.6 = B
2.6A=26
A=10
4) 200*h1=h2*40*25
h1=5*h2
5米
5) (22-2)*(12-2)*(11-2)
=1800cm^3
收錄日期: 2021-04-12 23:04:16
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