大梅 2/7×1/6÷6

2/7×1/6÷6  

2/7×1/6÷6

=2/7×1/6×1/6
=1/21×1/6
=1/126

2/7÷（）=1/10×（）=6/5×（）=20÷（）=1

2/7÷（2/7）=1/10×（10）=6/5×（5/6）=20÷（20）=1
除法是除以他本身等于1
乘法是乘以他的倒数等于1

1/3-(0.875*2/13+1除6又1/2除8)*1又6/7

1/3-(0.875*(2/13)+1除6又1/2除8)*1又6/7=1/3-(875/1000*(2/13)+1/(13/2)/8)*13/7
=1/3-(7/8*(2/13)+1/(13*4))*13/7=1/3-(7/(13*4)+1/(13*4))*13/7
=1/3-2/13*(13/7)=1/3-2/7=1/21

[-2/3]+[+0.25]+[-1/6]-[+1/2]=__?

- 1/12

（- 2/3 )+ (+ 0.25) + ( - 1/6) - (+ 1/2)

您好！
(- 2/3 )+ (+ 0.25) + ( - 1/6) - (+ 1/2)
=0.25-2/3-1/6-1/2
=0.25-(2/3+1/6+1/2)
=1/4-4/3
=-(4/3-1/4)
=-(13/12)

已知2/2*4=1/2-1/4，2/4*6=1/4-1/6，求1/2*4+1/4*6+……+1/48*50的和

1/2*4+1/4*6+……+1/48*50
=1/2*(2/2*4+2/4*6+.....+2/48*50)
=1/2*(1/2-1/4+1/4-1/6+......+1/48-1/50)
=1/2*(1/2-1/50)
=1/2*(25-1)/50
=12/50
=6/25

(2a^2/3 *b^1/2)(-6a^1/2*b^1/3)/(-3a^1/6*b5/6)

(2a^2/3 *b^1/2)(-6a^1/2*b^1/3)/(-3a^1/6*b5/6)
=12a^7/6*b^5/6 /(3a^1/6*b5/6)
=4a

Ⅹ+1/4=2/5 1/6

Ⅹ+1/4=2/5 +1/6
x=2/5+1/6-1/4
x=24/60+10/60-15/60
x=19/60
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方程1/4 /6x=2/7

6x=（1/4）/（2/7）
6x=7/8
x=7/48
可追问，有帮助望采纳。

1/2/6/7 算24点

1: (1 + 7) ÷ 2 × 6
2: ((1 + 7) ÷ 2) × 6
3: (1 + 7) ÷ (2 ÷ 6)
4: (1 - 7) × (2 - 6)
5: (1 + 7) × 6 ÷ 2
6: ((1 + 7) × 6) ÷ 2
7: (1 + 7) × (6 ÷ 2)
8: (2 - 6) × (1 - 7)
9: 2 × (6 - 1 + 7)
10: 2 × ((6 - 1) + 7)
11: 2 × (6 - (1 - 7))
12: 2 × (6 + 7 - 1)
13: 2 × ((6 + 7) - 1)
14: 2 × (6 + (7 - 1))
15: 2 × (7 - 1 + 6)
16: 2 × ((7 - 1) + 6)
17: 2 × (7 - (1 - 6))
18: 2 × (7 + 6 - 1)
19: 2 × ((7 + 6) - 1)
20: 2 × (7 + (6 - 1))
21: (6 - 1 + 7) × 2
22: ((6 - 1) + 7) × 2
23: (6 - (1 - 7)) × 2
24: (6 × (1 + 7)) ÷ 2
25: 6 × (1 + 7) ÷ 2
26: 6 × ((1 + 7) ÷ 2)
27: 6 ÷ 2 ×(1 + 7)
28: (6 ÷ 2) × (1 + 7)
29: 6 ÷ (2 ÷ (1 + 7))
30: (6 - 2) × (7 - 1)
31: 6 ÷ 2 ×(7 + 1)
32: (6 ÷ 2) × (7 + 1)
33: 6 ÷ (2 ÷ (7 + 1))
34: (6 + 7 - 1) × 2
35: ((6 + 7) - 1) × 2
36: (6 + (7 - 1)) × 2
37: (6 × (7 + 1)) ÷ 2
38: 6 × (7 + 1) ÷ 2
39: 6 × ((7 + 1) ÷ 2)
40: 6 × (7 - (1 + 2))
41: 6 × (7 - 1 - 2)
42: 6 × ((7 - 1) - 2)
43: 6 × (7 - (2 + 1))
44: 6 × (7 - 2 - 1)
45: 6 × ((7 - 2) - 1)
46: (7 + 1) ÷ 2 × 6
47: ((7 + 1) ÷ 2) × 6
48: (7 + 1) ÷ (2 ÷ 6)
49: (7 - (1 + 2)) × 6
50: (7 - 1 - 2) × 6
51: ((7 - 1) - 2) × 6
52: (7 + 1) × 6 ÷ 2
53: ((7 + 1) × 6) ÷ 2
54: (7 + 1) × (6 ÷ 2)
55: (7 - 1 + 6) × 2
56: ((7 - 1) + 6) × 2
57: (7 - (1 - 6)) × 2
58: (7 - 1) × (6 - 2)
59: (7 - (2 + 1)) × 6
60: (7 - 2 - 1) × 6
61: ((7 - 2) - 1) × 6
62: (7 + 6 - 1) × 2
63: ((7 + 6) - 1) × 2
64: (7 + (6 - 1)) × 2