Let the weight of the empty box be $x$ kg. The weight of the apples is three times the weight of the box, so the weight of the apples is $3x$ kg.

The total weight of the box and the apples is 15 kg. Therefore, we can set up the equation:

$x + 3x = 15$

Combine like terms:

$4x = 15$

Solve for $x$:

$x = \frac{15}{4} = 3.75 \, \text{kg}$

Final Answer:

The weight of the box without the apples is 3.75 kg.

Would you like more details or have any questions?

Here are 5 related questions for further exploration:

1. What is the weight of the apples alone?
2. How would the equation change if the weight of the apples were twice the weight of the box?
3. What is the total weight if the box's weight were increased by 20%?
4. How many such boxes would weigh a total of 100 kg?
5. If 25% of the apples were removed, what would be the new total weight?

Tip: When solving word problems, clearly define the variables and their relationships to avoid