1, and the sum of the inner angles of the polygon is 15840 degrees. How many polygons is this polygon? The sum of the inner angles of a polygon =(n-2) times 180 n-2 times180 =15840n-2 = 88n = 90, so it is a 90-sided polygon. There are two polygons A and B, and the sum of the sides and inner angles of polygon A is 2 times and 4 respectively. Let A be a 2x polygon and B be an x polygon (2x-2) *180 = 4 (x-2) *180, and x=3 is obtained, so A is a hexagon and B is a triangle. 3. The number of sides of two regular polygons is 1: 2, and the internal angle ratio is 2: 3, so the number of these two polygons should be less. The sum of the internal angles of the two polygons is (x-2) 180 and (2x-2) 180, respectively. Then the degrees of each inner angle are: a:(x-2) 180/x and b: (2x-2) 65438+. So one polygon is a quadrilateral and the other is an octagon. 4. A polygon with an internal angle of 120 degrees is _ _ _ _ _, and it * * * has _ _ diagonal lines, each with an internal angle of 120 degrees, so each internal angle is 60 degrees. Let this polygon have x sides (x-2) ×180 =120x180x-360 =120x60x = 360x = 6 hexagon with n diagonal lines: n * (n-3)/. Find the number of sides of two polygons. Let a polygon have n sides and another polygon have 5/2*n sides. According to the formula180 (x-2)+180 (5/2 * n-2) =1800n = 45/2 * n =10.

It is known that there are two odd numbers and one even number among the three numbers A, B and C, and n is an integer. If s = (a+n+1) (b+2n+2) (c+3n+3), what is the number of s?

S=(a+n+ 1)(b+2n+2)(c+3n+3)

Note that if b is even, then b+2n+2 is even, so s is even.

If b is odd, then a and c are odd and even.

At this time, the parity of a+n+ 1 and c+3n+3 is different, and their product is even, so s is even.

Therefore, s is always an even number.

At 100 yuan, I bought 100 pens, each 3 yuan for pencils, each 5 yuan for ballpoint pens and 5 red pens 1 yuan. Ask the number of each pen clearly.

Set x, y, z y, z pencils, ballpoint pens and red pens respectively.

x+y+z= 100

3x+5y+( 1/5)z= 100

x=200-2.4z

y = 1.4z- 100

Z is less than 250/3 and more than 500/7.

X, y, z, y and z are all positive integers.

Z=80 or 75

X=8 or 20, y= 12 or 5.

Party A and Party B take 54 cards in turn, and each person can take 1 ~ 4 cards at a time, but can't leave. It is stipulated that taking the last card is a loss, and Party A takes it first. Who has a winning strategy? Please provide a justification for the answer.

First of all, A takes three cards, and then B takes the number of 5 no matter how many cards he takes, that is, B takes 2 A for 3, B takes 1 A for 4, and finally B loses.

If A and B are reciprocal, and M and N are reciprocal, find the value of M÷?ab-(-n )÷?ab.

Because A and B are reciprocal, ab= 1.

M+n=0, because m and n are reciprocal.

That is, m ÷ ab-(-n) ÷ ab = m-(-n) = m+n = 0.

An electronic clock is installed in the bell tower of the railway station, and a small colored lamp is installed on the boundary of the clock face in minutes. At 9: 35: 20 in the evening, how many small color lights were installed at the A corner between the hour hand and the minute hand?

At 9: 35: 20, it is obvious that the minute hand is between 35 and 36. At this time, the position of the hour hand is calculated: the minute hand walks 60 squares and the hour hand walks 5 squares. So the hour hand goes (35.3 minutes (35 minutes and 20 seconds) /60)*5=2.94 square, so the hour hand is between 47 and 48, so there is a lantern 65438 in the included angle.