How many three digit numbers can be made up of 10 numbers from 0 to 9?

First of all, choose a hundred, not zero, so there are nine choices from 1 to 9, and the remaining nine numbers can be arranged at will. Choose two permutations from the nine numbers, which are 9 * 8, so there are a total of 9 * 9 * 8 = 648. The key to this problem is that the first one cannot be zero

How many five digit numbers can be made up of numbers 0, 3, 5, 7 and 9, and what is the calculation formula

There are four methods of C (4) 1 = 4 and the remaining four. It is a permutation problem. There are 24 methods of a (4) 4 = 4 × 3 × 2 × 1
There are 96 methods of C (4) 4 * a (4) 4 = 24 × 4 = 96

0.1.2.3.7.8.9. Fill in the following formula () + () = () - () = () () the number can not be repeated in the first grade of primary school

8+9=20-3=17

RELATED INFORMATIONS

1. With the 10 numbers from 0 to 9, you can make up the even number of three digits without repetition 1. When the mantissa is 2, 4, 6 and 8, the number of bits combined is 4. Because the hundreds cannot be 0, the number of bits combined is 8, and the number of bits combined is 8 × 8 × 4 = 256 2. When the mantissa is 0, the combination of 100 bits is 9, the combination of 10 bits is 8, and the total number of combinations is 9 × 8 × 1 = 72 Total 256 + 72 = 328 On the basis of this classification, I have a question: why should we take the hundred first, if we take the ten first. Process 1: there are 9 combinations of ten (ten can take 0), and 7 combinations of hundred
2. It is known that ABC is a three digit number, and the sum of the other five three digits composed of a, B and C is 2006, The sum of the other five three digits composed of a, B and C is 2006, so the difference between the largest and the smallest of the six three digits is
3. Use 1,3,5,7,9 to form a formula of multiplying three digits by two digits, and write the formula of maximum product
4. Please fill in the brackets below with the nine numbers 1 - 9 to make the equation true. Each number can only be used once （）÷（）=（）÷（）=（）（）（）÷（）（ )
5. Fill in the multiplication sign or division sign in the nine brackets of the following formula to make the equation true 10 () 9 () 8 () 7 () 6 () 5 () 4 () 3 () 2 () 1 = 64 / 7
6. 1-9 these figures, four digits divided by two digits equal to three digits, can not be repeated!
7. In 123456789, multiply one of the four numbers by the other four digits. The number cannot be repeated
8. Two math problems, tell me the formula and why The water content of 100 tons of grapes measured in Xinjiang is 99% of 100, and that of grapes transported to Nanjing is 98% of 100. How many tons are left after the grapes are transported to Nanjing? There are two bags of rice, and the weight of the second bag is 4 / 7 of the second bag. If 8 and 2 / 5 kg are taken out of the first bag and put into the second bag, the two bags are equal, How many kilos each of these two bags of rice weighs? Tell me the formula and why. You can give more points. Please give details. Thank you
9. 52 students went boating, a total of 11 boats, including 6 people for each big boat and 4 people for each small boat?
10. How do 1, - 2,2,3 count as 24 o'clock
11. How many three digit numbers can these numbers make up
12. What kind of multiplication formula can 2 + 2 + 2 + 4 be written?
13. How many multiplication formulas can you write for the whole ten times one digit, Lu 240?
14. In a multiplication, if one factor is increased by 5, the product is increased by 100. If the other factor is increased by 4, the product is increased by 120 Can you directly divide 100 by 5 to get 20, and then divide 120 by 4, the answer is 600
15. 785 these three numbers and decimal point and multiplication sign, which decimal formula can you write
16. Given that A1 = 9, A3 + A8 = 0 in the arithmetic sequence {a n}, find 1. The general term formula of the sequence {a n} 2. When n is the value, the first few terms of the number weight {a} and Sn take the maximum And find the maximum value
17. Use three four five six seven eight six numbers to form two three digit numbers, make the product of these two three digit numbers maximum, how to arrange, and explain the thinking
18. Use 0,1,2,3,4,5 to form the number without repetition. (1) how many four digit numbers can be formed; (2) how many four digit numbers can be formed (2) How many four digits can be divided by 5? (3) How many odd and even numbers can be composed of four digits arranged alternately.
19. How to make the nine numbers 123456789 into two four digit numbers, one of which is a multiple of the other, and nine digits cannot be repeated This is the homework of grade three in primary school. There are 123456789 nine numbers. One four digit number is multiplied by one one digit number. The other four digit number is nine numbers. It can't be repeated
20. How many of the 3 digits without repetition are composed of 1.2.3.4.5.6