After five trials, Ronald and Maria calculated the experimental density of aluminum to be 2.54 g/cm3. If the actual density of aluminum is 2.70 g/cm3, what was their percent error, rounded to the nearest whole number?

a. 5%

b. 6%

c. 9%

d. 16%

Percent error is a statistical tool used for evaluating precision. It is expressed as:

Percent error = | (experimental value - theoretical value) / theoretical value | x 100%

Experimental value represents the calculated value while the theoretical value represents the known value. A percent error value which is approaching zero means that your experimental value is close to the known value. Which can possibly mean that you have precise measurements. Calculations are as follows:

Percent Error = | (2.54 - 2.70) / 2.70 | x 100 = 5.93%

Thus, the answer is b. 5.93%.