Roger has a nail that is 12 centimeters long. He measures and records the length of the nail as 15 centimeters. What is the percent error in Roger's measurement? 15% 17% 20% 25%

First, calculate the difference between 15 and 12. The operation, subtraction, will give us the answer of 3. Then, divide the calculated value by 12 since this it the theoretical length of the nail. Multiply the quotient by 100% to arrive to the final answer. That is (3/12) (100%). The final answer to this item is 25% which is the last choice.