Assuming you don't want repetition: You have 9 options for the first position (any of the digits except 0), 9 options for the second digit (any digit, expect the digit you used in the first position), and 8 options for the third position (any digit, except the two you used before). Therefore you have 9 x 9 x 8 options. If repetition is allowed, you have 9 x 10 x 10 options.
Three different 10-digit numbers with a 7 in the millions place could be: 1234567890, 9876543210, and 7401234567. Each of these examples maintains the 7 in the millions place while varying the other digits to create unique numbers.
I take it that you want to make three digits numbers with 8,7,3, and 6 without repetition. The first digit cane be selected from among 4 digits, the second from 3 digits, the third digit from 2, hence the number of three digit numbers that can be formed without repetition is 4 x 3 x 2 = 24
To form three-digit even numbers from the set {2, 3, 5, 6, 7}, we can use the digits 2 or 6 as the last digit (to ensure the number is even). For each case, we can choose the first two digits from the remaining four digits. For three-digit numbers, there are 2 options for the last digit and (4 \times 3 = 12) combinations for the first two digits, resulting in (2 \times 12 = 24) even numbers. For four-digit even numbers, we again have 2 options for the last digit. The first three digits can be selected from the remaining four digits, giving us (4 \times 3 \times 2 = 24) combinations for each last digit. Thus, there are (2 \times 24 = 48) even four-digit numbers. In total, there are (24 + 48 = 72) three-digit and four-digit even numbers that can be formed from the set.
For the first digit there would be 4 options For the second digit there would be 3 options for the third digit there would be 2 options Thus 4*3*2 = 24 three digit numbers can be formed if each digit can only be used once in a 3 digit number made.
To form a three-digit number using the digits 1-7, we can choose any of the 7 digits for each of the three places (hundreds, tens, and units). Therefore, the total number of 3-digit combinations can be calculated as (7 \times 7 \times 7), which equals 343. Thus, there are 343 different three-digit numbers that can be formed using the digits 1-7.
512
Three different 10-digit numbers with a 7 in the millions place could be: 1234567890, 9876543210, and 7401234567. Each of these examples maintains the 7 in the millions place while varying the other digits to create unique numbers.
from 100 to 999 it is 900
27 three digit numbers from the digits 3, 5, 7 including repetitions.
Forming three three digit numbers that use the numbers 1-9 without repeating, the highest product possible is 611,721,516. This is formed from the numbers 941, 852, and 763.
81 As there are no limits stated then you can have a number comprising a repeated single digit (such as 2222), two pairs of numbers (e.g. 2244) or three different numbers (such as 2462). The first digit can be one of any of the 3 numbers. The second digit can be one of any of the three numbers, as can the third digit and also the fourth. Then you can have 3 x 3 x 3 x 3 = 81 different 4-digit numbers using the three given numbers.
I take it that you want to make three digits numbers with 8,7,3, and 6 without repetition. The first digit cane be selected from among 4 digits, the second from 3 digits, the third digit from 2, hence the number of three digit numbers that can be formed without repetition is 4 x 3 x 2 = 24
48 of them if digits may not be repeated. 100 if they can.
Any 3 out of 4 = 4. Each set can be arranged 6 ways so 24 different numbers.
Choose from 4 for the first number, 3 for the second number, and 2 for the third number. Therefore there are 4*3*2 = 24 three digit numbers can be formed from 3769 if each digit is used only once.
24 of them. So we have a 2 or 6 in the unit position, therefore (2)(4)(3) = 24 even three-digit numbers, can be formed.
For the first digit there would be 4 options For the second digit there would be 3 options for the third digit there would be 2 options Thus 4*3*2 = 24 three digit numbers can be formed if each digit can only be used once in a 3 digit number made.