X piece
(x-2) is a multiple of 3.
It is also a multiple of 5.
X is a multiple of 7.
X-2 can be 15, 30, 45, 60, 75, 90 (because a circle has dozens of holes, it will not be greater than 100).
X is17,32,47,62,77,92.
Only 77 is 7.
Multiple of
So there are 77 holes.
website construction
Answer adoption rate: 22.7%
2009-02-05
15:59
1. The length and width of a cuboid are all 5cm. 12cm, and its volume is five times that of a cube with a side length of 6cm. What is the height of this cuboid?
2. What is the height of a cylinder with a base diameter of 20 cm and a height of 36 cm?
3. If a commodity with a cost of 55 yuan is priced in 200 yuan, will it lose money if the merchant sells it at a 30% discount? What if it is sold at a 20% discount?
4. A clothing store is going to sell a certain brand of sweaters at a discount of 60% due to the season change, and each sweater can still make a profit in 30 yuan. If the purchase price of this sweater is 90 yuan per piece, please ask for the original price tag of this sweater!
5. A pair of leather shoes will be marked with a price increase of 30% based on the cost price, and then sold at a 20% discount due to seasonal reasons. The price is 208 yuan. What is the cost price of this kind of leather shoes?
6. Girls in the extracurricular group originally accounted for one-third of the total number of students in the group. After four female students joined, they just accounted for half of the total number of the group. What was the original number of extracurricular groups?
7. If a commodity is priced in 550 yuan, it can still get a profit of 10% after being sold at a 20% discount. What is the purchase price of this commodity?
8. At two o'clock, the hour hand and the minute hand are at right angles?
Dream on. `★ ~ ~
Answer adoption rate: 12. 1%
2009-02-05
16:48
At 7 o'clock, the minute hand is at right angles.
Charming boy
Answer adoption rate: 19.0%
2009-02-05
17:33
Question 2 is 9.
That point po- 倳メ
2009-02-05
17:38
There are still 60 congruent triangles, but I can't send the map, so there are only 60 factorizations. Some may be due to some problems with the monitor. Please forgive me.
1、3a？ -6ax=
2 、( x+ 1)x-5x=
3、xy+2x-5y- 10=
4、2x？ 2y-2x-2y+ 1=
5、2xy-2xy-3x-2y+2y- 1=
6 、-6ax+ 18a？
=
7、20a？ bc-9a？ BC? -20abc？
=
8、2a-5x+2ax-5
=
9、4+4x-25x-25
=
10 、( 1-xy)2-(y-x)2
=
1 1、2mx-2m-x+ 1
=
12
5 times? -45=
13、a？ -2ab+b？ - 1=
14、2y(x-y)+2z(y-x)= 1
15、8 1x？ -9x=
16、x？ +x+y？ -y-2xy=
17 、( 2x+ 1)(x-3)-(2x+ 1)(x-5)= 1
18、x？ -Really? -5x-5y=
19、x？ -Really? +2yz-z？ =
20 、( x
-2)(x-3)+(x
-2)(x+4)= 1
2 1、7(x- 1)
+4(x- 1)(y+2)
=
22、4x？ +4xy+y？ -4x-2y-3=
23、9x？ -x=
24、
=
25、4
=
26、7mx-4x-7m+4
=
27、 1-x2
=
28, 5 meters
(a+b)-a-b
=
29. A.
(x-y)–b(y-x)= 1
30、(-2) 1999
+(-2)2000=
3 1 、( x+2)(x-3)+(x+2)(x+4)= 1
32、3x？ -6x=
33、49x？ -25=
34、x？ -5x+6=
35、2 1-3x=
36、24x-24=
37、
(x-6)-(x-6)(x+)
6)=
38 、( x+2)(x-5)-(x+2)(x-3)
39、2 1+28x+49=
40、4+35x+49
x？ =
4 1、2ax？ -3x+2ax-3=
42、9x？ -66x+ 12 1=
43、8-2x？ =
44、x？ -x- 12
=
45、9x？ -30x+25=
46,-20 times? +9x+20=
47、 12x？ -29x+ 15=
48、36x？ +39x+9=
49、3x？ -3 1x-22=
50、9x？ -35 times? -4
x=
5 1 、( 2x+ 1)(x+ 1)+(2x+ 1)(x-3)= 1
52、2ax？ -7x+2ax-7=
53、x(y+2)-x-y- 1=
54 、( x？ -3x)+(x-3)2=
55、4x？ -52x+ 169=
56、8-2x？ =
57、x？ - 1=
58、x？ +2x-xy-2y=
59、4x？ - 12x+5=
60、2 1x？ - 19x-22=