Question

In a four-digit number, the sum of the thousands and hundred digits is 3.

The tens digit is 4 times the hundreds digit.
The ones digit is seven more than the thousands digit.
No two digits are equal.
What is the four-digit number?

Answer 1

Answer: 2149

Step-by-step explanation: If the sum of the first two digits is 3, the choices must be 1 and 2 (or 2 and 1) In order to satisfy the other specifications, "the tens digit is 4 times the hundreds digit." the hundreds digit can't be 2 because that would make the tens dight 8. and the ones digit would also have to 8 in order to satisfy the "seven more than the thousands digit" which would be a 1. And that violates the condition, "No two digits are equal."

So the only possible combination is 2149

4 is 4 times 1

9 is 7 +2