How do you calculate percentage error, i think you take the error and divide it by your measurement x100?

Question

but how do you know how much error the thing you use has

any help will be appreciated

Answer 1

To find the percent error you take the actual value - experimental value and divide this difference by the actual value and multiply by 100.

So, (actual - experimental) / experimental   x 100.

Answer 2

(actual reading - experimental reading) / experimental reading x 100.

here actual reading refers to the reading found out bytheoryy...i mean on paper.