Final answer:
By utilizing the given conditions and algebraic expression, it is determined that the three-digit number where the sum of its digits is 12, the tens digit is 2 more than the hundreds digit, and the units digit is the sum of the tens and hundreds of digits, is 246.
Step-by-step explanation:
The question asks us to find a three-digit number based on specific conditions related to its digits. To solve this, let's list out the given conditions and assign variables to each digit of the number:
- The sum of the digits is 12.
- The tens digit (t) is 2 more than the hundreds digit (h).
- The unit digit (u) is equal to the sum of the tens and hundreds digits (t + h).
Expressing the conditions algebraically, we get:
- h + t + u = 12
- t = h + 2
- u = h + t
From the second condition, we can replace t in the other two equations:
- h + (h + 2) + u = 12
- u = h + (h + 2)
Combining the equations, we find:
2h + 2 + u = 12
u = 2h + 2
Then, we simplify and solve for h:
2h + 2 + (2h + 2) = 12
4h + 4 = 12
4h = 8
h = 2
Substituting h back into the conditions, we get:
- t = 2 + 2 = 4
- u = 2 + 4 = 6
Therefore, the three-digit number, based on the given conditions, is 246.