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There are ten small balls in red, yellow, blue and white. Put them in a cloth bag and find five at a time. How many of them have the same color? 9, 13. What's the rule
5÷4=1..1
therefore
1 + 1 = 2 colors are the same;
9÷4=2..1
therefore
2 + 1 = 3 colors are the same;
13÷4=3..1
3 + 1 = 4 colors are the same;
Rule: if the remainder is greater than or equal to 1, then the result is: at least quotient + 1 balls have the same color
There are ten small balls in red, yellow, blue and white. Put them in a cloth bag and find five at a time. How many of them have the same color?
Another (2) if you touch nine balls at a time, how many of them are the same color?
There are ten small balls in red, yellow, blue and white. Put them in a cloth bag and find five at a time. How many of them have the same color?
Four colors are equivalent to four drawers, five at a time, five things into four drawers, at least two of the same color!
Another (2) if you touch nine balls at a time, how many of them are the same color?
Four colors are equivalent to four drawers. Nine drawers can be found at one time. Nine things can be put into four drawers. At least three drawers have the same color!
There are 10 red, yellow and blue balls in the box. It is required to close your eyes to ensure that no less than four balls of the same color can be touched at a time. Then how many balls should be touched at least?
(4-1) × 3 + 1, = 3 × 3 + 1, = 9 + 1, = 10
Wide angle questions in sixth grade mathematics of primary school [based on the basic training of people's Education Press (Shandong Province Press)]
Xiao Ming has 40 triangle, rectangle and Pentagon cards. These cards have 156 corners. The number of rectangle and Pentagon cards is the same. How many of the three cards are there
Only learned x, nothing else
Let the number of triangles, rectangles and pentagons be x, y and Z respectively
x+y+z=40,3x+4y+5z=156,y=z
The solution is: x = 16, y = 12, z = 12
For a manuscript, it takes 6 hours for a to type it alone, and 10 hours for B to type it alone. Now, after a few hours of typing alone, it takes 7 hours for B to finish it because of something, so it's time for a to type______ Hours
Let a work alone for X hours, from the meaning of the question: 16x + (7-x) × 110 = 1 & nbsp; & nbsp; 16x + 710-110x = 1 & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; 115x = 1-710, & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp
Solve a question: 1,2,6,16,44, (), 328
120. The rule is: the difference between the two adjacent numbers of the first five numbers is 1,4,10,28 respectively, and the last digit is equal to twice the sum of the first two numbers. For example: 10 = (1 + 4) * 2. According to this, it can be deduced that the difference between () and 44 is (10 + 28) * 2 = 76, so () is 120
The following group of numbers are arranged in regular order: 0, 2, 8, 26, 80 What is the sixth number?
The following group of numbers are arranged in regular order: 0, 2, 8, 26, 80 What is the number in 2006?
3^(1-1)-1=0
3^(2-1)-1=2
3^(3-1)-1=8
3^(4-1)-1=26
3^(5-1)-1=80
3^(6-1)-1=242
The general formula of the sequence is observed
a(n)=3^(n-1)-1,
So the number 2006 is 3 ^ 2005-1
A set of data arranged according to the rule: 3, - 5,7, - 9,..., what is the nth number?
3 is 2 × 1 + 1
-5 is - (2 × 2 + 1)
7 is 2 × 3 + 1
-9 is - (2 × 4 + 1)
So when n is odd, the nth number is 2n + 1
When n is even, the nth number is - (2n + 1)
The sum is [- 1 ^ (n + 1)] (2n + 1), n ∈ n
Some negative numbers are arranged as follows, observe their rules, and answer which row and column will the number - 100 be in? [explain why]
First column second column third column fourth column fifth column
-2 -3 -4 -5
-9 -8 -7 -6
-10 -11 -12 -13
-17 -16 -15 -14
…… …… ……
The fourth column
There are four numbers in each line, regardless of symbols. The smallest ones are 2, 6, 14
The law is 2 + 4x (x = 0, 1, 2,...)
When x = 24, it is 2 + 4x = 98,
So the four numbers in the line of - 100 are - 98, - 99, - 100, - 101
When x = 0,2,4, that is, even number,
The positions of the four numbers are the second column, the third column, the fourth column and the fifth column,
So - 100 is in the fourth column
Observe the arrangement of these numbers and answer which row and column the number - 100 is in
First column second column third column fourth column fifth column
-2 -3 -4 -5
-9 -8 -7 -6
-10 -11 -12 -13
-17 -16 -15 -14
…… …… ……
Regardless of minus sign:
Each row has four numbers
100÷4=25
Since it starts with - 2, - 100 is on line 26
When the number is odd, it is from small to large, such as the first line 2 3 4 5
When the number of lines is even, it is from large to small, such as the second line 9 8 7 6
26 is even, so line 26 goes from large to small
therefore
-100 is in line 26, column 2
RELATED INFORMATIONS
- 1. There are 10 red, yellow and blue balls in your pocket. Close your eyes and make sure you can touch many four balls of the same color at a time. How many can you touch What's the formula
- 2. In a box, there are 20 balls of red, yellow, blue, green and white. At least touch a few balls to ensure that there are two balls of each color? Come on the sooner the better Within an hour
- 3. If four different balls are put into four red, yellow, blue and green boxes, there is exactly one empty box
- 4. There are six red balls and six blue balls of the same size in the box. 1. If you want to find two balls of the same color, how many balls at least? 2. There must be three balls of the same color in order to touch them. How many balls should we touch at least? 3. If you want to touch the ball, there must be two colors. How many balls should you touch at least?
- 5. There are 24 table tennis balls in one box 1. If two-thirds of the students are sent, how many are left? 2. If you send one sixth of the whole box to the students first, and then one third of the whole box to the students, how many will be sent to the students?
- 6. How many ways to put four different balls into three different boxes?
- 7. There are 158 cards in red and black. They are arranged in the order of five red cards and four black cards. What's the last color? Ask to explain + answer (urgent!
- 8. There are a total of 2012 balls in the three piles. If Gao takes the same number of balls from each pile, there are still 17 balls left in the second pile, and the number of balls left in the first pile is twice that of the third pile, then the third pile is the original pile______ A small ball
- 9. The black-and-white beads are white and black, forming an equilateral triangle. When the difference between the number of black-and-white beads in the equilateral triangle is 30, how many should be arranged on each side of the triangle?
- 10. A box of beads, the first time out of the total number of 15 and 4, the second time out of the remaining 14 and 3, the third time out of the remaining 13 and 2, the fourth time out of the remaining 12 and 1, then there is still one in the box. How many original beads in the box?
- 11. There are 10 red, yellow, blue and white balls each, mixed in a cassette, and at least one touch out______ In order to ensure that there are six balls in the same color
- 12. There are 10 red, yellow, blue and white balls, which are mixed and put in a cassette. At least how many balls must be found at a time to ensure that there are 6 balls in the same color
- 13. If a number is a multiple of 2 and 3, it must be a multiple of 6______ ．
- 14. Look at the following table ~ and answer what numbers x ~ and y are 0 1 1 1 0 0 1 2 2 5 5 x 2 0 0 5 y 14 16 16
- 15. A math problem. 1.2.7.14.23.34. How to find the law
- 16. Observe the following table 1 2 3 4 The first line 2 3 4 5 The second line 3 4 5 6 The third line 4 5 6 7 The fourth line The first, second, third and fourth columns guess that the number at the intersection of the sixth row and the sixth column should be______ , the number at the intersection of row N and column n should be______ (expressed by a formula containing a positive integer n)
- 17. Number game: the first line 28 7 7 6, the second line 9 9 8 8, the third line () 5 13 16, 5 B, 17 C, 19 D, 47 which one Let's talk about the reasoning process
- 18. It is necessary to arrange 2 / 3, 5 / 6, 5 / 13 and 11 / 18 in descending order
- 19. Take 6 / 11, 10 / 17, 15 / 26, 5 / 8, 12 / 19 from small to large, which score is at the top
- 20. The numbers 1, - 1 / 2,1 / 3, - 1 / 4,1 / 5, - 1 / 6 are arranged as follows according to certain rules, First line 1 Second line - 1 / 2 1 / 3 The third line - 1 / 4 1 / 5 - 1 / 6 The fourth line 1 / 7 - 1 / 8 1 / 9 - 1 / 10 The fifth line 1 / 11 - 1 / 12 1 / 12 - 1 / 14 1 / 15 ………… ……………… ………… So, can you write 10 numbers from left to right in line 20?