If 2 and 21 / 8 divided by M = 2 and 2 / 1, then M multiplied by 1 and 20 / 7 =?

If 2 and 21 / 8 divided by M = 2 and 2 / 1, then M multiplied by 1 and 20 / 7 =?

1 and 2 / 7

The square of a number is 56.25. What is the number?
I'm from junior high school

In fact, it can be estimated
What number multiplies itself by 25? It's 5. So the decimal part is 5
In the integral part, the square of 8 is 64, and the square of over. 7 is 49. Then try 7.5 × 7.5, and you will get the answer

111. (n 1) is it a square number

There is a simple proof method
The square of any odd number is divided by four to make one,
When n > 1, 111. (n 1) is divided by 4 to get 3,
So when n > 1, 111. (n 1) is not a square number

The sum of the squares of three consecutive positive integers is 875

Three continuous positive integers X-1, x, x + 1, x > 1
(x-1)²+x²+(x+1)²=875
x²-2x+1+x²+x²+2x+1=875
3x²=873
x²=873/3=291
X = 17.0587.. is not a positive integer,
The way of thinking is like this, the 875 you gave may be wrong

Both numbers are composite numbers, the greatest common factor is 1, and the least common multiple is 180. These numbers are () and (), () and ()

The greatest common factor is 1, so the two numbers are coprime. That is to say, if the multiplication of two numbers = 180180 = 2 * 2 * 3 * 3 * 5, then 4 and 45, 9 and 20

On a 60cm long note, draw a red dot every 3cm from the left end, and then draw a red dot every 4cm from the left end. The two ends of the note are not drawn. Finally, how many red dots are there in the note?

(60 ／ 3-1) + (60 ／ 4-1) = 19 + 14 = 33 (pieces) because within 60, there are 12, 24, 36 and 48 points in the common multiple of 3 and 4, that is, four points overlap, so it should be: 33-4 = 29 (pieces); a: there are 29 red points on the note

Common factors and common multiples in mathematical problems
In a = 4b, the greatest common factor of a and B is () and the least common multiple is ()

The greatest common factor is B and the least common multiple is a

For five consecutive integers, the sum of squares of the first three numbers equals the sum of squares of the last two numbers

Let these five consecutive integers be n, N + 1, N + 2, N + 3, N + 4, N2 + (n + 1) 2 + (n + 2) 2 = (n + 3) 2 + (n + 4) 2, and the solution is n = 10 or n = - 2. When n = 10, these five numbers are 10, 11, 12, 13, 14. When n = - 2, these five numbers are - 2, - 1, 0, 1, 2

In the natural number of 100, what is the sum of all the numbers that cannot be divided by 8

101×50＝5050

How many natural numbers from 1 to 1000 can't be divisible by 13 or 31? Why?

13 * 31 = 403, and 806. Except these two numbers, none of them can be divisible by 13 and 31 at the same time. There are 998