Let the current ages of the siblings be as follows:

• The age of the oldest sibling = $x$.
• The age of each of the younger two twins = $y$ (since they are twins, their ages are the same).

In 2 years, their ages will be:

• Oldest sibling: $x + 2$
• Each twin: $y + 2$

The average age of the siblings in 2 years will be:

$\text{Average age} = \frac{(x + 2) + (y + 2) + (y + 2)}{3} = \frac{x + 2 + y + 2 + y + 2}{3} = \frac{x + 2y + 6}{3}$

According to the problem, this average age is equal to the current age of the oldest sibling, $x$. Thus, we have the equation:

$\frac{x + 2y + 6}{3} = x$

To solve for $x$ and $y$, first multiply both sides by 3 to eliminate the denominator:

$x + 2y + 6 = 3x$

Now, simplify and solve for $y$:

$2y + 6 = 2x$ $2y = 2x - 6$ $y = x - 3$

Thus, the age of each of the younger siblings is 3 years less than the age of the oldest sibling.

Conclusion:

The age difference between the oldest sibling and the youngest sibling is 3 years.

Would you like more details or have any questions?

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Here are 5 related questions to deepen your understanding:

1. What will be the average age of the siblings 5 years from now?
2. If the oldest sibling is 10 years old, how old are the younger siblings?
3. How does the age difference between siblings affect the average age over time?
4. What happens to the average age if one sibling’s age is doubled in the future?
5. How can this problem be modified if the twins were different ages?

Tip: When solving problems involving averages, translating conditions into algebraic equations often helps simplify the relationships between variables.