Could someone explain the methodology for Java lesson 20?

Question

I've been hitting my head against this wall for a bit now, but just don't understand the methodology.

You have an amount
You need to subtract 10% of that amount from that amount 3 times.
Then you need to output what is left of the amount.

I just have no idea how to get what's left as an output, and would appreciate help.

Answer 1

If you have an amount of 5000:

10% of 5.000 = 500
5000 - 500 = 4500

10% of 4500 = 450
4500 - 450 = 4050

10% of 4050 = 405
4050 - 405 = 3645

left -> 3645

What is 10% from n? It is the same as n * 0.1

Hope this helps.