Currently, the average age of the five family members is 25 years. This implies that the total age of all five members is:

$25 \times 5 = 125 \text{ years}$

After 5 years, each family member will be 5 years older, so the total increase in age for the family will be:

$5 \times 5 = 25 \text{ years}$

Thus, the total age of all five family members after 5 years will be:

$125 + 25 = 150 \text{ years}$

Now, to find the average age after 5 years, we divide the total age by the number of family members:

$\frac{150}{5} = 30 \text{ years}$

So, the average age of the family members after 5 years will be 30 years.

Would you like a detailed breakdown of the steps, or do you have any questions?

Here are some related questions:

1. What would be the average age if the family had 6 members instead?
2. How does average age change if some members age differently than others?
3. What is the total increase in age for 10 years for each member?
4. How does the average age relate to each member’s individual age?
5. How would the calculation change if another member joined the family?

Tip: When calculating averages, multiplying the average by the number of items can help find the total sum, making it easier to adjust for future values.