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The problem of expanding thinking in primary school mathematics is urgent ~ ~ (it is better to have a process)
1, natural number 2007 decomposition, found that only the product of 3,3,223 can be equal to 2007.

Suppose 2007 is the product of five natural numbers, then the combination of these five natural numbers may be

1.2007、 1、 1、 1、 1

2.223、9、 1、 1、 1

3.223、3、3、 1、 1

Similarly, if 2007 is the product of four natural numbers, then the combination of these four natural numbers may be

1.2007、 1、 1、 1

2.223、9、 1、 1

3.223、3、3、 1

The difference between the two numbers in the inscription is the largest, so it can only be subtracted from the largest number and the smallest number.

Therefore, a = 2007+1+1,and B=223+3+3+ 1.

A-B=277 1 is the maximum value.

2. If one number is X and the other number is x+5, there are two cases: 1 and two numbers have a common divisor of 5; 2. Two numbers are coprime; If the common divisor of two numbers is 5, obviously their minimum common multiple is also a multiple of 5, and the difference between the minimum common multiple and the maximum common divisor must be a multiple of 5. Obviously, 203 is not a multiple of 5, so the first case is not satisfied, so the two numbers are coprime; The greatest common divisor of two prime numbers is 1, so the least common multiple of these two numbers is 203+ 1=204. Because these two numbers are coprime, the least common multiple of these two numbers is their product, so the prime factor of multiplying these two numbers by 202,202 is 204 = 2 * 2 * 3 * 65438+.

3. 1 1 to 20, there are121618 65438 65438 65438/kloc.

4. Subtract the original four digits to get 2007.72, which means that he clicked the decimal point before the hundredth digit, so 2007.72/99=20. 28

So this number is 20. 28* 100=2028

5. Cyclic decimals are written as abc/999 and 58, so decimals can be divided into 999 factors of 3, 3, 3 and 37. Because the sum is 58, the denominator can only be 37 and 27. Because it is a true fraction, the numerator is smaller than the denominator, so the numerator is 58-37=2 1 and the denominator is 37, so it can be divided by 567/97.

6. The fractional part is (17.88-15.64)/(8-1) = 0.32.

The integer part is 15.64-2*0.32= 15.

Yes, so this number is 15+0.32= 15.32.

7. The multiplier is 20.06/(20.066 …-20.06) =1003, so the correct answer is 20.066 … *1003 = 210.130.

8、0.3455……+0.346 1 1……-0.345=0.34666……