A few elementary school math problems! Answer before 10 o clock! Thank you!

1.The decimal system is relative to the binary counting system, and it is the most commonly used counting method in our daily life; The counting method in which the rate of advance between every two adjacent counting units is ten" is called "decimal notation".

Comparison of the size of integers: first look at the number of digits, the number with more digits is larger; The number of digits is the same, and from the highest digit, the number on the same digit is larger.

2) Comparison of the size of the decimal number first compare the integer part of the two numbers, and the number with the larger integer part is larger; The integer part is the same, and then look at their decimal part, from the high position, according to the number comparison, the number on the same digit is larger.

3) Comparison of the size of the fraction: the fraction with the same denominator is larger; fractions with the same numerator, fractions with smaller denominator are larger; Scores with different denominators, the first score is compared.

3.The numerator and denominator of the fraction expand (or shrink) by the same multiple at the same time, adding 0 to the end of the decimal or removing 0 to keep it the same size.

4.Look at what is behind your decimal point.

For example, if you move another bit, it will increase by 10 times.

Moving left is reduced by a factor of 10.

5.Prime numbers, composite numbers.

Prime numbers are also called prime numbers. The number of prime numbers is infinite. Composite Number:

In addition to 1 and itself, the divisor of a number has other divisors, and this number is called a composite number. 2 is not a composite number, and 1 is neither prime nor composite. The prime factor is the divisor:

Factors of a composite number, and these factors are all prime numbers

Multiples, factors.

In division, if the dividend is divided by the divisor, and the quotient obtained is a natural number with no remainder, then the dividend is said to be a multiple of the divisor, and the divisor is the factor of the dividend.

I don't know about decimal notation.

How to compare the size of two numbers: see which number is larger A=v=

3: All numbers = v = and both can count clams.

4: The decimal size will become larger or smaller.

5: There is a number after it. To say the meaning...It's also all counting=v=

There is a formula for this problem: (first term, last term) number of terms: 2, so 2+4+6+8+10+...96+98+100=2+100+（4+98）+（8+96）+.50+52）=102×50÷2

Add that this has a total of 50 numbers, and +96....50+52 adds a total of 50 2 to 102, so you get 102 50 2

It's very simple, 1 to 100 is equal to 5050, and even numbers are more than the previous odd number, and there are 50 even numbers in 1,100, so (5050-50) 2=2500

If you look at the direction of the arrow, take one from both sides to the middle side, and finally divide the 50 numbers into 25 groups, I think.

1-100 is a total of 100 numbers, all are even numbers, 100 2=50 pairs.

Half find the middle, 100, half 50, 50+52

That is, how many even numbers are from 2 to 50, which is 50 2 = 25 pairs.

Mention 2 times and obviously 2 times (1+2+......50）

First: For example, 2--10, there are several, 5 is, it is even, 12--20 is also 5, a total of 50 numbers, except for 50, 100, a total of 24 pairs. 2 Second, this problem is not solved in this way, it should be 2+, 6+94....

50,100 plus that, for reference,

Because 2 100 has 50 even numbers, there are 25 pairs in total.

Do you have to be 2+100=102 and 4+98=102? Wouldn't you be 2+98=100, 4=96=100? 2 to 100 won't be counted, you won't be 2 to 10. And then don't you just make the value again? It's stupid.

Use the same equation 1Sum = (first term + last term) * number of terms 2 2Number of items = (last term - first term) Tolerance +1 Solution to this problem:

100-2) 2+1=50 (number of terms) (100+2)*50 2=2500

Out of 100 numbers, 50 are even and 50 are odd.

Half of 50, i.e. 25 102