A few sixth grade math problems are in a hurry, and there are really no points

Let's talk about the results, and if you need the process, you can talk about it.

1.The 50th number is 2.

2.(1) This number is from the left, and the 1995th number is 1.

2) 800 is the 2290th to 2292nd number of this number.

The first question is 3, the first cycle is 2*3=6 numbers, and the second cycle is 3*3=9 numbers,......The last round is 15 numbers, and the 50th number is the 3rd 3

Question 2 (1) There are 9 digits composed of one-digit numbers, and a total of (99-10+1)*2=180 digits composed of two-digit numbers, so 1995-180-9=1806,1806 3=602,602-1+100=701, so the 1995th digit is 1

2) I don't understand the meaning of ......

1。The 50th number is 2.

2。The 1995th number is 1.

800 is the 2280th to 2282nd number of this number.

The first question was originally intended to be done with equations, but it was a bit troublesome, so you arrange the numbers in groups: 6 9 12 15 18 21 ......Add them one by one, 6+9+12+15=42, 6+9+12+15+18=60, so 50 is in an array of 18, and 18 is 5 1, 6 2, 7 3, so the number is 2

Question 2. 1) 9 single digits, 90 tens digits, 900 hundred digits, ......Obviously, the 1995th number is a certain number in the hundreds, (1995-9-2*90) 3=602, so this number is the last number in the 602nd hundred, that is, 1 in 671

2) 800 is the 701st hundred, so the three numbers in 800 are the 2290th, 2291st, and 2292nd respectively (I don't understand this little question very well, so I can only do this).

Choose me, choose me.

It seems that there is no pattern to be found, but if there is a rule of judging the size, it is still possible.

The three numbers on the triangle angle are up, left, and right (here is a simple definition), find the pattern:

If left and right, then the middle number = up * left + (right + right - left) if right left, then the middle number = up * left - (right + right - left) for example, 78 = 12 * 6 + (5 + 6-5), 30 = 2 * 17 - (3 + 3 - 2) and so on, the middle number of the third triangle is 23 * 4 - (7 + 7-4) = 82 I don't know if it's right, just for reference.

The law is: (the numerator does not change, the denominator is added to one).

The law is: (the denominator does not change, the numerator is added to or subtracted from the first two as follows: 9 10,,10 10,,8 10,,11 10,,7 10).

The law is: ( The denominator does not change, the numerator is added to five, such as: 3 20,,8 20,,13 20,,18 20,,23 20).

52 Question B

Sum the up, down, left and right.

The first one goes up and down.

15 or so 12

Poor 318126

9 From this the last one is inferred.

25 should be 12

So the up and down sum is 37

The number to be filled in is 37--18=19

The next question is 4 different

The following is 543 in order

21 Therefore, choose C

Question 1: b

18+?-12+13)=12, get? =19 plus 3 in turn

Question 2: Molecule C: Add 4 in turn

Denominator: Decrease sequentially

52 is 19. The sum of the two numbers horizontally is 3n different from the sum of the verticals.

The question at the bottom. The difference above is 4

The following is 543 in order

21 So choose C

Now this little ascension is going against the sky.

52.The first left and right and for 12

The upper and lower sum is 15

Difference 3; The second left and right sum is 12, the upper and lower sum is 18, and the difference is 6; The third left and right sum is 21, and the upper and lower sum is 9; So the third left and right sum is 12 and the upper and lower sum is 12, the left and right sum is 25, and the following number is 37-18 = 19

54.Add 4 to each of the above terms, the third number should be 15, and the difference between every two numbers below is 5,4,3,2,1, so the second number is 10

1.Because the first one is -2 bigger than the right, the second is 1 bigger than the right, and the third is 4 bigger than the right

2.Add 4 each time above, it is 15, and below it is -5, -4, -3, -2, -1, it is 10, choose c

Choose B and C for each of the two questions

Question 1: (8-4)-(9-6)=1

So choose 17, and each of the above questions is +4 in turn

Below is 136

1015 is reversed, 1=1, 3=1+2, 6=1+2+3, 10=1+2+3+4, 15=1+2+3+4+5

Question 1: b

18+?-12+13)=12, get? =19 plus 3 in turn

Question 2: Molecule C: Add 4 in turn

Denominator: Decrease sequentially

52 Question B Sum of Up, Down, Left and Right First Up and Down 15 Left and Right 12 Difference 3

18 12 630 21 9 to infer that the last 25 should be 12, so the sum of up and down is 37, and the number to be filled in is 37—-18=19

The next question is 4 on the top, and 5 4 3 2 1 on the bottom, so C is chosen

Choose B and C for each of the two questions

Question 1: (8-4)-(9-6)=1 (7-5)-(10-8)=0 (11-10)-(15-15)=1 (13-12)-(18-17)=0 So choose 17

Question 2 Each of the above is +4 in turn, and the lower one is 1 3 6 10 15 upside down, 1 = 1, 3 = 1 + 2, 6 = 1 + 2 + 3, 10 = 1 + 2 + 3 + 4, 15 = 1 + 2 + 3 + 4 + 5

52.The first left and right sum is 12, the upper and lower sum is 15, and the difference is 3; The second left and right sum is 12, the upper and lower sum is 18, and the difference is 6; The third left and right sum is 21, and the upper and lower sum is 9; So the third left and right sum is 12 and the upper and lower sum is 12, the left and right sum is 25, and the following number is 37-18 = 19

54.Add 4 to each of the above terms, the third number should be 15, and the difference between every two numbers below is 5,4,3,2,1, so the second number is 10

52 is 19. The sum of the two numbers horizontally is 3n different from the sum of the verticals.

The bottom question is 4 at the top, and the difference at the bottom is 5 4 3 2 1, so choose C

Now this little ascension is going against the sky.

1.Because the first one is -2 bigger than the right, the second is 1 bigger than the right, and the third is 4 bigger than the right

2.Add 4 each time above, it is 15, and below it is -5, -4, -3, -2, -1, it is 10, choose c

You see, this is called Yang Hui Triangle, and you know it when you go to junior high school.

Each number is equal to the sum of the two numbers on the top left and right (except for 1), so you can see that one is 10 and the other is 5.

This kind of finding the pattern is relatively simple, as long as you are serious and repeatedly look at the picture, I wish you good results.

(1) Look at the figure, find the rule to fill in the blanks, and know from the figure (count from left to right) that the first space (below 6) is filled in (10), and the second space (below 1) is filled in (5).

1+4+6+4+1=16

The two spaces add up to 14

It can be seen from this. The first space (below 6) is filled in (9) (6+3).

The second space (below 1) is filled in (5) (14-9).

The number below this one is the sum of the numbers on its left and right shoulders in the previous row, so the first empty should be 10 (4+6) and the second empty is 5 (1+4).

This is symmetrical.,The first space is filled in (10),The second space is filled in (5).。

1/42/3

23 46 (multiply three, multiply two, add three, multiply two, add three, multiply two.......)）