The problem states:

"Eight years ago, Mr. Karim was $\frac{1}{3}$ of the age he will be after 10 years. What is his age now?"

Let $x$ be Mr. Karim's current age. Therefore:

• Eight years ago, his age was $x - 8$.
• In 10 years, his age will be $x + 10$.

According to the given information: $x - 8 = \frac{1}{3} (x + 10)$

Now, let's solve this equation step by step.

Step 1: Multiply both sides by 3 to eliminate the fraction:

$3(x - 8) = x + 10$ $3x - 24 = x + 10$

Step 2: Bring all terms involving $x$ to one side:

$3x - x = 10 + 24$ $2x = 34$

Step 3: Solve for $x$:

$x = \frac{34}{2} = 17$

Thus, Mr. Karim is 17 years old now.

The correct answer is $\boxed{17}$.

Would you like further clarification on any part of the solution?

Here are 5 related questions to explore further:

1. If Mr. Karim was $\frac{1}{4}$ of the age he will be in 12 years, how old is he now?
2. What will be Mr. Karim’s age in 20 years if he is currently 17?
3. If Mr. Karim’s age eight years ago was half of his current age, how old is he now?
4. How old will Mr. Karim be if he is three times the age he was ten years ago?
5. How old was Mr. Karim four years ago if he is now 17?

Tip: When working with age problems, setting up a clear equation based on the relationship between past and future ages is key to finding the correct solution.