In a batch of 60 shipments, you find 3 address digits incorrect. What is the error rate?

• A. 3%
• B. 5%
• C. 6%
• D. 2%

Answer: (B)

Error rate is the share of items with an error relative to the total. Here, 3 incorrect address digits occur in a batch of 60 shipments, so the rate is 3 ÷ 60 = 0.05, or 5%. The other percentages don’t fit: 3% of 60 would be 1.8 errors, 6% would be 3.6 errors, and 2% would be 1.2 errors, none of which are whole shipments.