In science class, Mr. Brodell’s students were directed to weigh a 400-gram mass on the balance scale. Erika weighed the object and reported 420 grams. What is the percent error of the weight of Erika's object?

Answer 1

The percent error can be calculated using the formula:

percent error = (|measured value - actual value| / actual value) * 100

In this case, the measured value is 420 grams and the actual value is 400 grams.

percent error = (|420 - 400| / 400) * 100
percent error = (20 / 400) * 100
percent error = 0.05 * 100
percent error = 5%

Therefore, the percent error of the weight of Erika's object is 5%.