To solve this problem:

• Initial amount from your sister: Php 2,395
• Weekly savings: Php 190
• Number of weeks: 7 weeks

The total amount you will have after 7 weeks can be calculated as: $\text{Total amount} = \text{Initial amount} + (\text{Weekly savings} \times \text{Number of weeks})$

Let's compute it step by step:

$\text{Total amount} = 2,395 + (190 \times 7)$

Now I will calculate this.After 7 weeks, you will have Php 3,725.

Would you like more details or have any questions?

Here are some related questions for further exploration:

1. How many more weeks are needed to reach Php 4,500?
2. What if the weekly savings were increased to Php 250? How much would you have after 7 weeks?
3. How much will you have after 10 weeks at the current saving rate?
4. What is the difference between your savings and the cost of the skateboard after 7 weeks?
5. How much more do you need to save after 7 weeks to buy the skateboard?

Tip: Tracking your savings each week can motivate you to reach your goal faster!