Imagine having the initial number 100. If I enter 50 in another input, it should add 50 to 100. However, if I then change the value from 50 to 80, the total should be 180 and not 230.
The goal is always to add numbers to the original sum, not the new value.
Instead of following this pattern:
this.number=+ 50 = 150 , this.number=+ 80 = 230;
We want something like this:
this.number=+ 50 = 150 , this.number=+ 80 = 180;