What is the range of values for the measurement 500 + 4%

Four percent of 500 is 20. Thus, we have the range of values (500-20, 500+20), or (480, 520).

If the number is 500

that means that 1% is 5 because 5 x 100 = 500. That means

that 4% is 5 + 5 + 5 + 5 which is 20. That means that 500 + - 4% is equal

to 500 + - 20, meaning that the range is from 480 to 520,

which is 40 whole numbers