Arithmetic problems, such as the number of 0.25g, the kilogram is 10, but the total number is 10 divided by 0.25 times 1000 and so on. Why divide the kilogram and the kilogram? Thank you,

Arithmetic problems, such as the number of 0.25g, the kilogram is 10, but the total number is 10 divided by 0.25 times 1000 and so on. Why divide the kilogram and the kilogram? Thank you,

Because 1kg = 1000g, so 10kg = 10 * 1000g, so number = total amount / single weight = 10 * 1000 / 0.25 = 40000

Set a six digit. 1abcde multiplied by 3, it becomes. Abcde1______ ．

According to the above analysis: 142857 × 3 = 428571

Let 6-digit 1abcde multiply by 3 to abcde1, and then find 6-digit 1adcde
As high as above

Let ABCDE be X
1ABCDE=100000+ABCDE=100000+X
ABCDE1=10ABCDE+1=10X+1
3*(100000+X)=10X+1
300000+3X=10X+1
7X=299999
X=42857
1ABCDE=100000+ABCDE=100000=42857=142857

If M satisfies the relation √ 3x + 5y-2-m + √ 2x + 3y-m = √ x-199 + y * √ 199-x-y, try to find the value of M
Note: "tick" is the root sign

Happy New Year!

If M is suitable for the relation, then √ 3x + 5y-2-m + √ 2x + 3y-m = √ x-199 + y times √ 199-x-y, try to determine the value of M

Where x-199 + y under the root sign indicates that x + y-199 is greater than or equal to 0 (the definition of numbers under the root sign)
The formula 199-x-y under the root indicates that 199-x-y is greater than or equal to 0
We know that 199 = x + y from these two results
The right side of the above equation is equal to 0, so the left side is also 0
Then 3x + 5y-2-m = 0
2X + 3y-m = 0 under root sign
And X + y = 199
m=201 x=396 y= -197

[3x + 5y-2-m] + [2x + 3y-m] = [x-199 + y] * [199-x-y] find the value of M

3x+5y-2-m>=0 2x+3y-m>=0x-199+y>=0 199-x-y>=0 -(x-199+y)>=0x-199+y=0 x+y=1993x+5y-2-m=0 m=3x+5y-2 m=3(x+y)+2y-2 m=3*199+2y-22x+3y-m=0 m=2x+3y m=2(x+y)+y 2m=4*199+2ym=19...

18a2-32b2-18a+24b．

Can't (x-2y) * (- x-2y) (2y-x) * (- x-2y) (- 2y-x) * (x + 2Y) be calculated with the square difference formula

(- 2y-x) * (x + 2Y) can not be calculated by square difference formula. (- 2y-x) (x + 2Y) = - (x + 2Y) (x + 2Y) = - (x + 2Y) &# 178; = - (X & # 178; + 4xy + 4Y & # 178;) (x-2y) = - (x-2y) (x + 2Y) = - (x-2y) = - (x-2y) (x + 2Y) = - (X & # 178;) = 4Y & # 178; - X & # 178; (2y-x-2y) = - (2y-x) (2Y + X)

Which of (x-2y) (- x-2y) and (x-2y) (- x + 2Y) can't use the square difference formula

(x-2y) (- x + 2Y) can't be used. The latter refers to a minus sign. The two of them are the same

It is known that the average of nine numbers is 72. After one number is removed, the average of the remaining numbers is 78, and the number removed is 78______ ．

The sum of 9 numbers: 72 × 9 = 648, the sum of the remaining 8 numbers: 78 × 8 = 624, the number removed is: 648-624 = 24