For a four - digit number greater than 1000, the sum of the digits in the thousands, hundreds and tens places is 17. The sum of the digits in the hundreds, tens and units places is 18. The digit in the tens place is 4 more than the digit in the units place. What is the difference between the largest and the smallest possible values of the number?

For a four - digit number abcd, the sum of the thousands, hundreds and tens digits is 17, while the sum of the hundreds, tens and units digits is 19. The tens digit is one less than twice the thousands digit. Find the difference between the largest and the smallest possible values of the number.

How many three - digit positive integers N satisfy all of the following conditions? - N is divisible by 7. - The sum of the digits of N is divisible by 7. - All three digits of N are non - zero and pairwise distinct.

Let N be a four - digit number with distinct digits allowed or repeated digits allowed. The number obtained by reversing its digits exceeds N by 2178. Also, N is divisible by 9. How many such four- digit numbers are possible?

TITA} A three-digit positive integer $\overline{abc}$ (with $a \neq 0$) satisfies all of the following simultaneously:

Find the sum of all three-digit numbers $\overline{abc}$ satisfying these conditions.

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Geometry / Mensuration

Find the three - digit number N, with all digits non - zero, such that N exceeds the number formed by reversing its digits by 396, N is divisible by 9, and the product of its digits is 168.