How do I n value?

In my game I want to make my character encounter boss every multiple of 50 (score) global variable (50,100,150,200,etc). How do I translate this ?

Use a second variable that adds with score but resets to 0 when it hits 50 :)

Use a second variable that adds with score but resets to 0 when it hits 50 :)

Thank you it worked :)