The units digit of a two digit number exceeds twice the tens digit by 1. Find the number if the sum of its digits is 10.
18 and 38
18 and 38
Oh, what a happy little question! The greatest 6-digit number where the digit in the thousands place is twice the digit in the tens place is 986,432. And the smallest 6-digit number following the same rule is 164,823. Isn't it wonderful how numbers can dance together in such a harmonious way?
AB If B = x, then A = x + 4 Also, A = 2x -1 So that, 2x - 1 = x + 4 x = 5 B = 5, A = 9 So AB = 95
120 5-digit numbers can be made with the numbers 12345.
18 and 38
18 and 38
Assuming that the first digit of the 4 digit number cannot be 0, then there are 9 possible digits for the first of the four. Also assuming that each digit does not need to be unique, then the next three digits of the four can have 10 possible for each. That results in 9x10x10x10 = 9000 possible 4 digit numbers. If, however, you can not use the same number twice in completing the 4 digit number, and the first digit cannot be 0, then the result is 9x9x8x7 = 4536 possible 4 digit numbers. If the 4 digit number can start with 0, then there are 10,000 possible 4 digit numbers. If the 4 digit number can start with 0, and you cannot use any number twice, then the result is 10x9x8x7 = 5040 possilbe 4 digit numbers.
Oh, what a happy little question! The greatest 6-digit number where the digit in the thousands place is twice the digit in the tens place is 986,432. And the smallest 6-digit number following the same rule is 164,823. Isn't it wonderful how numbers can dance together in such a harmonious way?
None. The sum of one digit can't be twice the size of the digit.
216.
A proper 2-digit number (which must be smaller than 100) cannot be twice a 10-digit number (which must be larger than 999,999,999).
AB If B = x, then A = x + 4 Also, A = 2x -1 So that, 2x - 1 = x + 4 x = 5 B = 5, A = 9 So AB = 95
216
120 5-digit numbers can be made with the numbers 12345.
100012
1